Sample records for model involves iterative

  1. Iterative-build OMIT maps: map improvement by iterative model building and refinement without model bias

    SciTech Connect (OSTI)

    Terwilliger, Thomas C., E-mail: terwilliger@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Grosse-Kunstleve, Ralf W.; Afonine, Pavel V.; Moriarty, Nigel W.; Adams, Paul D. [Lawrence Berkeley National Laboratory, One Cyclotron Road, Building 64R0121, Berkeley, CA 94720 (United States); Read, Randy J. [Department of Haematology, University of Cambridge, Cambridge CB2 0XY (United Kingdom); Zwart, Peter H. [Lawrence Berkeley National Laboratory, One Cyclotron Road, Building 64R0121, Berkeley, CA 94720 (United States); Hung, Li-Wei [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2008-05-01T23:59:59.000Z

    An OMIT procedure is presented that has the benefits of iterative model building density modification and refinement yet is essentially unbiased by the atomic model that is built. A procedure for carrying out iterative model building, density modification and refinement is presented in which the density in an OMIT region is essentially unbiased by an atomic model. Density from a set of overlapping OMIT regions can be combined to create a composite ‘iterative-build’ OMIT map that is everywhere unbiased by an atomic model but also everywhere benefiting from the model-based information present elsewhere in the unit cell. The procedure may have applications in the validation of specific features in atomic models as well as in overall model validation. The procedure is demonstrated with a molecular-replacement structure and with an experimentally phased structure and a variation on the method is demonstrated by removing model bias from a structure from the Protein Data Bank.

  2. Iterative build OMIT maps: Map improvement by iterative model-building and refinement without model bias

    SciTech Connect (OSTI)

    Los Alamos National Laboratory, Mailstop M888, Los Alamos, NM 87545, USA; Lawrence Berkeley National Laboratory, One Cyclotron Road, Building 64R0121, Berkeley, CA 94720, USA; Department of Haematology, University of Cambridge, Cambridge CB2 0XY, England; Terwilliger, Thomas; Terwilliger, T.C.; Grosse-Kunstleve, Ralf Wilhelm; Afonine, P.V.; Moriarty, N.W.; Zwart, P.H.; Hung, L.-W.; Read, R.J.; Adams, P.D.

    2008-02-12T23:59:59.000Z

    A procedure for carrying out iterative model-building, density modification and refinement is presented in which the density in an OMIT region is essentially unbiased by an atomic model. Density from a set of overlapping OMIT regions can be combined to create a composite 'Iterative-Build' OMIT map that is everywhere unbiased by an atomic model but also everywhere benefiting from the model-based information present elsewhere in the unit cell. The procedure may have applications in the validation of specific features in atomic models as well as in overall model validation. The procedure is demonstrated with a molecular replacement structure and with an experimentally-phased structure, and a variation on the method is demonstrated by removing model bias from a structure from the Protein Data Bank.

  3. Iterative model-building, structure refinement, and density modification with the PHENIX AutoBuild Wizard

    E-Print Network [OSTI]

    Terwilliger, T. C.; Los Alamos National Laboratory, Mailstop M888, Los Alamos, NM 87545, USA; Lawrence Berkeley National Laboratory, One Cyclotron Road, Building 64R0121, Berkeley, CA 94720, USA; Department of Haematology, University of Cambridge, Cambridge CB2 0XY, England

    2008-01-01T23:59:59.000Z

    Iterative model-building, structure refinement, and densitytool for iterative model- building, structure refinement andusing RESOLVE or TEXTAL model- building, RESOLVE statistical

  4. ITER

    SciTech Connect (OSTI)

    Cowley, Steve

    2005-10-10T23:59:59.000Z

    This year six international partners have signed up to construct the first burning plasma experiment -- ITER -- in the South of France.It is over 50 years since the beginning of national programs to produce controlled fusion energy. The challenge of fusion energy has proven harder than was first anticipated. In this Colloquium Steve Cowley from UCLA will explain the scientific issues and how the difficulties have been overcome.

  5. Assessing the Power Requirements for Sawtooth Control in ITER Through Modelling and Joint Experiments

    E-Print Network [OSTI]

    Assessing the Power Requirements for Sawtooth Control in ITER Through Modelling and Joint Experiments

  6. STELLOPT Modeling of the 3D Diagnostic Response in ITER

    SciTech Connect (OSTI)

    Lazerson, Samuel A

    2013-05-07T23:59:59.000Z

    The ITER three dimensional diagnostic response to an n=3 resonant magnetic perturbation is modeled using the STELLOPT code. The in-vessel coils apply a resonant magnetic perturbation (RMP) fi eld which generates a 4 cm edge displacement from axisymmetry as modeled by the VMEC 3D equilibrium code. Forward modeling of flux loop and magnetic probe response with the DIAGNO code indicates up to 20 % changes in measured plasma signals. Simulated LIDAR measurements of electron temperature indicate 2 cm shifts on the low field side of the plasma. This suggests that the ITER diagnostic will be able to diagnose the 3D structure of the equilibria.

  7. Japan, EU adamant about their proposals to host ITER, put off negotiations to next year; Joint construction plan involving Japan,

    E-Print Network [OSTI]

    Japan, EU adamant about their proposals to host ITER, put off negotiations to next year; Joint construction plan involving Japan, U.S. South Korea also emerging NIHON KEIZAI, December 20, 2004 Japan are likely to enter a crucial stage early in the next year. In addition to Japan and the EU, the United

  8. Final Report - Modeling Results For the ITER Cryogenic Fore Pump

    SciTech Connect (OSTI)

    Pfotenhauer, John M; Zhang, Dongsheng

    2014-03-31T23:59:59.000Z

    A numerical model characterizing the operation of a cryogenic fore-pump (CFP) for ITER has been developed at the University of Wisconsin – Madison during the period from March 15, 2011 through June 30, 2014. The purpose of the ITER-CFP is to separate hydrogen isotopes from helium gas, both making up the exhaust components from the ITER reactor. The model explicitly determines the amount of hydrogen that is captured by the supercritical-helium-cooled pump as a function of the inlet temperature of the supercritical helium, its flow rate, and the inlet conditions of the hydrogen gas flow. Furthermore the model computes the location and amount of hydrogen captured in the pump as a function of time. Throughout the model’s development, and as a calibration check for its results, it has been extensively compared with the measurements of a CFP prototype tested at Oak Ridge National Lab. The results of the model demonstrate that the quantity of captured hydrogen is very sensitive to the inlet temperature of the helium coolant on the outside of the cryopump. Furthermore, the model can be utilized to refine those tests, and suggests methods that could be incorporated in the testing to enhance the usefulness of the measured data.

  9. Application of the Asymptotic Iteration Method to a Perturbed Coulomb Model

    E-Print Network [OSTI]

    Paolo Amore; Francisco M. Fernandez

    2006-04-17T23:59:59.000Z

    We show that the asymptotic iteration method converges and yields accurate energies for a perturbed Coulomb model. We also discuss alternative perturbation approaches to that model.

  10. Modeling results for the ITER cryogenic fore pump

    SciTech Connect (OSTI)

    Zhang, D. S.; Miller, F. K.; Pfotenhauer, J. M. [University of Wisconsin-Madison, Madison, WI 53706 (United States)

    2014-01-29T23:59:59.000Z

    The cryogenic fore pump (CFP) is designed for ITER to collect and compress hydrogen isotopes during the regeneration process of torus cryopumps. Different from common cryopumps, the ITER-CFP works in the viscous flow regime. As a result, both adsorption boundary conditions and transport phenomena contribute unique features to the pump performance. In this report, the physical mechanisms of cryopumping are studied, especially the diffusion-adsorption process and these are coupled with standard equations of species, momentum and energy balance, as well as the equation of state. Numerical models are developed, which include highly coupled non-linear conservation equations of species, momentum and energy and equation of state. Thermal and kinetic properties are treated as functions of temperature, pressure, and composition. To solve such a set of equations, a novel numerical technique, identified as the Group-Member numerical technique is proposed. It is presented here a 1D numerical model. The results include comparison with the experimental data of pure hydrogen flow and a prediction for hydrogen flow with trace helium. An advanced 2D model and detailed explanation of the Group-Member technique are to be presented in following papers.

  11. Power Transmission From The ITER Model Negative Ion Source

    SciTech Connect (OSTI)

    Boilson, D. [Association EURATOM-DCU, PRL/NCPST, Glasnevin, Dublin 13 (Ireland); Esch, H. P. L. de; Grand, C.; Hemsworth, R. S.; Krylov, A. [Association EURATOM-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 St Paul-Lez-Durance (France)

    2007-08-10T23:59:59.000Z

    In Cadarache development on negative ion sources is being carried out on the KAMABOKO III ion source on the MANTIS test bed. This is a model of the ion source designed for the neutral beam injectors of ITER. This ion source has been developed in collaboration with JAERI, Japan, who also designed and supplied the ion source. Its target performance is to accelerate a D- beam, with a current density of 200 A/m2 and <1 electron extracted per accelerated D- ion, at a source filling pressure of 0.3 Pa. For ITER a continuous ion beam must be assured for pulse lengths of 1000 s, but beams of up to 3,600 s are also envisaged. The ion source is attached to a 3 grid 30 keV accelerator (also supplied by JAERI) and the accelerated negative ion current is determined from the energy deposited on a calorimeter. During long pulse operation ({<=}1000 s) it was found that the current density of both D- and H- beams, measured at the calorimeter was lower than expected and that a large discrepancy existed between the accelerated currents measured electrically and those transmitted to the calorimeter. The possibility that this discrepancy arose because the accelerated current included electrons (which would not be able to reach the calorimeter) was investigated and subsequently eliminated. Further studies have shown that the fraction of the electrical current reaching the calorimeter varies with the pulse length, which led to the suggestion that one or more of the accelerator grids were distorting due to the incident power during operation, leading to a progressive deterioration in the beam quality.. New extraction and acceleration grids have been designed and installed, which should have a better tolerance to thermal loads than those previously used. This paper describes the measurements of the power transmission and distribution using these grids.

  12. Modelling of Melt Damage of Tungsten Armour under Multiple Transients Expected in ITER and Validations Against JET-ILW Experiments

    E-Print Network [OSTI]

    Modelling of Melt Damage of Tungsten Armour under Multiple Transients Expected in ITER and Validations Against JET-ILW Experiments

  13. Iterative modelling, a new approach to the inversion of 1-D seismograms

    E-Print Network [OSTI]

    Raskin, Greg Steven

    1987-01-01T23:59:59.000Z

    by correcting the field trace. The plane wave impulse response is decayed by a factor of E" (which need only be approx- imately correct). This corrected impulse response approximates a point source impulse response but neglects differential decay between... schemes . 12 IV ITERATIVE MODELI. LNG 15 A. An iterative modelling procedure B. The initial model C. Smoothing the solution vector D. Parameter removal E. Residual error analysis as a means of parauseter addition . F. Reset ting the parameter...

  14. The 1D Iterative Model for Predicting Thermal Radiation from a Jet Fire

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    manuscript, published in "6. International Seminar on Fire and Explosion Hazards (FEH), Leeds : UnitedThe 1D Iterative Model for Predicting Thermal Radiation from a Jet Fire Leroy, G.* and Duplantier of the current jet fire models used in the accidental fire risks department are semi- empirical. They depend

  15. Characterization of the ITER model negative ion source during long pulse operation

    SciTech Connect (OSTI)

    Hemsworth, R.S.; Boilson, D.; Crowley, B.; Homfray, D.; Esch, H.P.L. de; Krylov, A.; Svensson, L. [Association EURATOM-CEA, CEA Cadarache, F-13108, St. Paul lez Durance (France); Association EURATOM-DCU, PRL/NCPST, Glasnevin, Dublin 13 (Ireland); Euratom/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Association EURATOM-CEA, CEA Cadarache, F-13108, St. Paul lez Durance (France)

    2006-03-15T23:59:59.000Z

    It is foreseen to operate the neutral beam system of the International Thermonuclear Experimental Reactor (ITER) for pulse lengths extending up to 1 h. The performance of the KAMABOKO III negative ion source, which is a model of the source designed for ITER, is being studied on the MANTIS test bed at Cadarache. This article reports the latest results from the characterization of the ion source, in particular electron energy distribution measurements and the comparison between positive ion and negative ion extraction from the source.

  16. TESTS OF 1-D TRANSPORT MODELS, AND THEIR PREDICTIONS FOR ITER

    E-Print Network [OSTI]

    Vlad, Gregorio

    of Technology, Göteborg, Sweden Abstract A number of proposed tokamak thermal transport models are tested foundation for extrapolations of energy confinement scalings to the ITER regime, 2) a means for optimizing Profile Database [2] which contains fully analyzed profile data, readily accessible, specified

  17. A Model-Based Iterative Algorithm for Dual-Energy X-Ray CT Reconstruction

    E-Print Network [OSTI]

    A Model-Based Iterative Algorithm for Dual-Energy X-Ray CT Reconstruction Ruoqiao Zhang, Jean, Senior Member, IEEE Abstract--Recent developments in dual-energy X-ray CT have shown a number of benefits the opportunity to reduce noise and artifacts in dual energy reconstructions. However, previous approaches

  18. Using Hidden Markov Models for Iterative Non-intrusive Appliance Monitoring

    E-Print Network [OSTI]

    Southampton, University of

    Using Hidden Markov Models for Iterative Non-intrusive Appliance Monitoring Oliver Parson, Hampshire, SO17 1BJ, UK {op106,sg2,mjw,acr}@ecs.soton.ac.uk Abstract Non-intrusive appliance load monitoring appliances. 1 Introduction Non-intrusive appliance load monitoring (NIALM), or energy disaggregation, aims

  19. Error Control of Iterative Linear Solvers for Integrated Groundwater Models

    E-Print Network [OSTI]

    Bai, Zhaojun

    gradient method or Generalized Minimum RESidual (GMRES) method, is how to choose the residual tolerance for integrated groundwater models, which are implicitly coupled to another model, such as surface water models the correspondence between the residual error in the preconditioned linear system and the solution error. Using

  20. Enabling rapid iterative model design within the laboratory environment 

    E-Print Network [OSTI]

    Clayton, Thomas F.

    2009-01-01T23:59:59.000Z

    This thesis presents a proof of concept study for the better integration of the electrophysiological and modelling aspects of neuroscience. Members of these two sub-disciplines collaborate regularly, but due to differing ...

  1. Integrated modelling of steady-state scenarios and heating and current drive mixes for ITER

    SciTech Connect (OSTI)

    Murakami, Masanori [ORNL; Park, Jin Myung [ORNL; Giruzzi, G. [CEA, IRFM, France; Garcia, J. [CEA Cadarache, St. Paul lex Durance, France; Bonoli, P. T. [Massachusetts Institute of Technology (MIT); Budny, R. V. [Princeton Plasma Physics Laboratory (PPPL); Doyle, E. J. [University of California, Los Angeles; Fukuyama, A. [Kyoto University, Japan; Ferron, J.R. [General Atomics, San Diego; Hayashi, N. [Japan Atomic Energy Agency (JAEA), Naka; Honda, M. [Japan Atomic Energy Agency (JAEA), Naka; Hubbard, A. [MIT Plasma Science & Fusion Center, Cambridge, MA 02139 USA; Hong, R. M. [General Atomics, San Diego; Ide, S. [Japan Atomic Energy Agency (JAEA), Naka; Imbeaux, F. [CEA Cadarache, St. Paul lex Durance, France; Jaeger, Erwin Frederick [ORNL; Jernigan, Thomas C [ORNL; Luce, T.C. [General Atomics, San Diego; Na, Y S [Seoul National University of Technology, Korea; Oikawa, T. [ITER Organization, Saint Paul Lez Durance, France; Osborne, T.H. [General Atomics, San Diego; Parail, V. [Association EURATOM-CCFE, Abingdon, UK; Polevoi, A. [ITER Organization, Saint Paul Lez Durance, France; Prater, R. [General Atomics; Sips, A C C [Max Planck Institute for Plasma Physics, Garching, Germany; Shafer, M. W. [University of Wisconsin, Madison; Snipes, J. A. [ITER Organization, Cadarache, France; St. John, H. E. [ITER Organization, Saint Paul Lez Durance, France; Snyder, P. B. [General Atomics, San Diego; Voitsekhovitch, I [UKAEA Fusion, Culham UK

    2011-01-01T23:59:59.000Z

    Recent progress on ITER steady-state (SS) scenario modelling by the ITPA-IOS group is reviewed. Code-to-code benchmarks as the IOS group's common activities for the two SS scenarios (weak shear scenario and internal transport barrier scenario) are discussed in terms of transport, kinetic profiles, and heating and current drive (CD) sources using various transport codes. Weak magnetic shear scenarios integrate the plasma core and edge by combining a theory-based transport model (GLF23) with scaled experimental boundary profiles. The edge profiles (at normalized radius rho = 0.8-1.0) are adopted from an edge-localized mode-averaged analysis of a DIII-D ITER demonstration discharge. A fully noninductive SS scenario is achieved with fusion gain Q = 4.3, noninductive fraction f(NI) = 100%, bootstrap current fraction f(BS) = 63% and normalized beta beta(N) = 2.7 at plasma current I(p) = 8MA and toroidal field B(T) = 5.3 T using ITER day-1 heating and CD capability. Substantial uncertainties come from outside the radius of setting the boundary conditions (rho = 0.8). The present simulation assumed that beta(N)(rho) at the top of the pedestal (rho = 0.91) is about 25% above the peeling-ballooning threshold. ITER will have a challenge to achieve the boundary, considering different operating conditions (T(e)/T(i) approximate to 1 and density peaking). Overall, the experimentally scaled edge is an optimistic side of the prediction. A number of SS scenarios with different heating and CD mixes in a wide range of conditions were explored by exploiting the weak-shear steady-state solution procedure with the GLF23 transport model and the scaled experimental edge. The results are also presented in the operation space for DT neutron power versus stationary burn pulse duration with assumed poloidal flux availability at the beginning of stationary burn, indicating that the long pulse operation goal (3000s) at I(p) = 9 MA is possible. Source calculations in these simulations have been revised for electron cyclotron current drive including parallel momentum conservation effects and for neutral beam current drive with finite orbit and magnetic pitch effects.

  2. An iterative stochastic ensemble method for parameter estimation of subsurface flow models

    SciTech Connect (OSTI)

    Elsheikh, Ahmed H., E-mail: aelsheikh@ices.utexas.edu [Center for Subsurface Modeling (CSM), Institute for Computational Engineering and Sciences (ICES), University of Texas at Austin, TX (United States); Dept. of Earth Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia); Dept. of Applied Mathematics and Computational Sciences, King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia); Wheeler, Mary F. [Center for Subsurface Modeling (CSM), Institute for Computational Engineering and Sciences (ICES), University of Texas at Austin, TX (United States)] [Center for Subsurface Modeling (CSM), Institute for Computational Engineering and Sciences (ICES), University of Texas at Austin, TX (United States); Hoteit, Ibrahim [Dept. of Earth Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia) [Dept. of Earth Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia); Dept. of Applied Mathematics and Computational Sciences, King Abdullah University of Science and Technology (KAUST), Thuwal (Saudi Arabia)

    2013-06-01T23:59:59.000Z

    Parameter estimation for subsurface flow models is an essential step for maximizing the value of numerical simulations for future prediction and the development of effective control strategies. We propose the iterative stochastic ensemble method (ISEM) as a general method for parameter estimation based on stochastic estimation of gradients using an ensemble of directional derivatives. ISEM eliminates the need for adjoint coding and deals with the numerical simulator as a blackbox. The proposed method employs directional derivatives within a Gauss–Newton iteration. The update equation in ISEM resembles the update step in ensemble Kalman filter, however the inverse of the output covariance matrix in ISEM is regularized using standard truncated singular value decomposition or Tikhonov regularization. We also investigate the performance of a set of shrinkage based covariance estimators within ISEM. The proposed method is successfully applied on several nonlinear parameter estimation problems for subsurface flow models. The efficiency of the proposed algorithm is demonstrated by the small size of utilized ensembles and in terms of error convergence rates.

  3. Interpretation of ensembles created by multiple iterative rebuilding of macromolecular models

    SciTech Connect (OSTI)

    Terwilliger, Thomas C., E-mail: terwilliger@lanl.gov [Los Alamos National Laboratory, Mailstop M888, Los Alamos, NM 87545 (United States); Grosse-Kunstleve, Ralf W.; Afonine, Pavel V.; Adams, Paul D.; Moriarty, Nigel W.; Zwart, Peter [Lawrence Berkeley National Laboratory, One Cyclotron Road, Building 64R0121, Berkeley, CA 94720 (United States); Read, Randy J. [Department of Haematology, University of Cambridge, Cambridge CB2 0XY (United Kingdom); Turk, Dusan [Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); Hung, Li-Wei [Los Alamos National Laboratory, Mailstop M888, Los Alamos, NM 87545 (United States)

    2007-05-01T23:59:59.000Z

    Heterogeneity in ensembles generated by independent model rebuilding principally reflects the limitations of the data and of the model-building process rather than the diversity of structures in the crystal. Automation of iterative model building, density modification and refinement in macromolecular crystallography has made it feasible to carry out this entire process multiple times. By using different random seeds in the process, a number of different models compatible with experimental data can be created. Sets of models were generated in this way using real data for ten protein structures from the Protein Data Bank and using synthetic data generated at various resolutions. Most of the heterogeneity among models produced in this way is in the side chains and loops on the protein surface. Possible interpretations of the variation among models created by repetitive rebuilding were investigated. Synthetic data were created in which a crystal structure was modelled as the average of a set of ‘perfect’ structures and the range of models obtained by rebuilding a single starting model was examined. The standard deviations of coordinates in models obtained by repetitive rebuilding at high resolution are small, while those obtained for the same synthetic crystal structure at low resolution are large, so that the diversity within a group of models cannot generally be a quantitative reflection of the actual structures in a crystal. Instead, the group of structures obtained by repetitive rebuilding reflects the precision of the models, and the standard deviation of coordinates of these structures is a lower bound estimate of the uncertainty in coordinates of the individual models.

  4. Iterative model-building, structure refinement, and density modification with the PHENIX AutoBuild Wizard

    SciTech Connect (OSTI)

    Los Alamos National Laboratory, Mailstop M888, Los Alamos, NM 87545, USA; Lawrence Berkeley National Laboratory, One Cyclotron Road, Building 64R0121, Berkeley, CA 94720, USA; Department of Haematology, University of Cambridge, Cambridge CB2 0XY, England; Terwilliger, Thomas; Terwilliger, T.C.; Grosse-Kunstleve, Ralf Wilhelm; Afonine, P.V.; Moriarty, N.W.; Zwart, P.H.; Hung, L.-W.; Read, R.J.; Adams, P.D.

    2007-04-29T23:59:59.000Z

    The PHENIX AutoBuild Wizard is a highly automated tool for iterative model-building, structure refinement and density modification using RESOLVE or TEXTAL model-building, RESOLVE statistical density modification, and phenix.refine structure refinement. Recent advances in the AutoBuild Wizard and phenix.refine include automated detection and application of NCS from models as they are built, extensive model completion algorithms, and automated solvent molecule picking. Model completion algorithms in the AutoBuild Wizard include loop-building, crossovers between chains in different models of a structure, and side-chain optimization. The AutoBuild Wizard has been applied to a set of 48 structures at resolutions ranging from 1.1 {angstrom} to 3.2 {angstrom}, resulting in a mean R-factor of 0.24 and a mean free R factor of 0.29. The R-factor of the final model is dependent on the quality of the starting electron density, and relatively independent of resolution.

  5. Iterative model building, structure refinement and density modification with the PHENIX AutoBuild wizard

    SciTech Connect (OSTI)

    Terwilliger, Thomas C., E-mail: terwilliger@lanl.gov [Los Alamos National Laboratory, Mailstop M888, Los Alamos, NM 87545 (United States); Grosse-Kunstleve, Ralf W.; Afonine, Pavel V.; Moriarty, Nigel W.; Zwart, Peter H. [Lawrence Berkeley National Laboratory, One Cyclotron Road, Building 64R0121, Berkeley, CA 94720 (United States); Hung, Li-Wei [Los Alamos National Laboratory, Mailstop M888, Los Alamos, NM 87545 (United States); Read, Randy J. [Department of Haematology, University of Cambridge, Cambridge CB2 0XY (United Kingdom); Adams, Paul D., E-mail: terwilliger@lanl.gov [Lawrence Berkeley National Laboratory, One Cyclotron Road, Building 64R0121, Berkeley, CA 94720 (United States); Los Alamos National Laboratory, Mailstop M888, Los Alamos, NM 87545 (United States)

    2008-01-01T23:59:59.000Z

    The highly automated PHENIX AutoBuild wizard is described. The procedure can be applied equally well to phases derived from isomorphous/anomalous and molecular-replacement methods. The PHENIX AutoBuild wizard is a highly automated tool for iterative model building, structure refinement and density modification using RESOLVE model building, RESOLVE statistical density modification and phenix.refine structure refinement. Recent advances in the AutoBuild wizard and phenix.refine include automated detection and application of NCS from models as they are built, extensive model-completion algorithms and automated solvent-molecule picking. Model-completion algorithms in the AutoBuild wizard include loop building, crossovers between chains in different models of a structure and side-chain optimization. The AutoBuild wizard has been applied to a set of 48 structures at resolutions ranging from 1.1 to 3.2 Å, resulting in a mean R factor of 0.24 and a mean free R factor of 0.29. The R factor of the final model is dependent on the quality of the starting electron density and is relatively independent of resolution.

  6. Improving macromolecular atomic models at moderate resolution by automated iterative model building, statistical density modification and refinement

    SciTech Connect (OSTI)

    Terwilliger, Thomas C., E-mail: terwilliger@lanl.gov [Mail Stop M888, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2003-07-01T23:59:59.000Z

    A procedure for iterative model-building, statistical density modification and refinement at moderate resolution (up to about 2.8 Å) is described. An iterative process for improving the completeness and quality of atomic models automatically built at moderate resolution (up to about 2.8 Å) is described. The process consists of cycles of model building interspersed with cycles of refinement and combining phase information from the model with experimental phase information (if any) using statistical density modification. The process can lead to substantial improvements in both the accuracy and completeness of the model compared with a single cycle of model building. For eight test cases solved by MAD or SAD at resolutions ranging from 2.0 to 2.8 Å, the fraction of models built and assigned to sequence was 46–91% (mean of 65%) after the first cycle of building and refinement, and 78-95% (mean of 87%) after 20 cycles. In an additional test case, an incorrect model of gene 5 protein (PDB code 2gn5; r.m.s.d. of main-chain atoms from the more recent refined structure 1vqb at 1.56 Å) was rebuilt using only structure-factor amplitude information at varying resolutions from 2.0 to 3.0 Å. Rebuilding was effective at resolutions up to about 2.5 Å. The resulting models had 60-80% of the residues built and an r.m.s.d. of main-chain atoms from the refined structure of 0.20 to 0.62 Å. The algorithm is useful for building preliminary models of macromolecules suitable for an experienced crystallographer to extend, correct and fully refine.

  7. Autonomous Car Fuzzy Control Modeled by Iterative Genetic Enrique Onieva, Javier Alonso, Joshue Perez, Vicente Milanes, Teresa de Pedro

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Autonomous Car Fuzzy Control Modeled by Iterative Genetic Algorithms Enrique Onieva, Javier Alonso. The unmanned control of the steering wheel is one of the most important challenges faced by researchers in this area. This paper presents a method of automatically adjusting a fuzzy controller to manage the steering

  8. Qualification of the ITER CS Quench Detection System using Numerical Modeling

    SciTech Connect (OSTI)

    Martovetsky, Nicolai N [ORNL; Radovinsky, Alexey L [ORNL

    2013-01-01T23:59:59.000Z

    Abstract The ITER Central Solenoid (CS) magnet needs to be protected against overheating of the conductor in the event of the occurrence of a normal zone (NZ). Due to a large amount of stored energy and slow NZ propagation, the NZ needs to be detected and the switchyard needs to open the breakers within 2 s after detection of the NZ. The CS will be discharged on a dump resistor with a time constant of 7.5 s. During operation of the CS and its interaction with the poloidal field (PF) coils and plasma current, the CS experiences large inductive voltages from multiple sources, including nonlinear signals from eddy currents in the vacuum vessel and plasma current variation, that make the task of detecting the resistive signal even more difficult. This inductive voltage needs to be cancelled by quench detection (QD) hardware (e.g., bridges, converters, filters, processors) and appropriate processing of the QD signals to reliably detect NZ initiation and propagation. Two redundant schemes are proposed as the baseline for the CS QD System: 1) A scheme with Regular Voltage Taps (RVT) from triads of Double Pancakes (DP) supplemented by Central Difference Averaging (CDA) and by digital suppression of the inductive voltage from all active coils (the CS and PF coils). Voltage taps are taken from helium outlets at the CS outer diameter. 2)A scheme with Cowound Voltage Taps (CVT) taken from cowound wires routed from the helium inlet at the CS inner diameter. Summary of results of the numerical modeling of the performance of both baseline CS QD systems is presented in this paper. Index Terms Quench detection, Central Solenoid, ITER

  9. Improved crystallographic models through iterated local density-guided model deformation and reciprocal-space refinement

    SciTech Connect (OSTI)

    Terwilliger, Thomas C., E-mail: terwilliger@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Read, Randy J. [University of Cambridge, Cambridge CB2 0XY (United Kingdom); Adams, Paul D. [Lawrence Berkeley National Laboratory, One Cyclotron Road, Building 64R0121, Berkeley, CA 94720 (United States); Brunger, Axel T. [Stanford University, 318 Campus Drive West, Stanford, CA 94305-5432 (United States); Afonine, Pavel V.; Grosse-Kunstleve, Ralf W. [Lawrence Berkeley National Laboratory, One Cyclotron Road, Building 64R0121, Berkeley, CA 94720 (United States); Hung, Li-Wei [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2012-07-01T23:59:59.000Z

    A density-based procedure is described for improving a homology model that is locally accurate but differs globally. The model is deformed to match the map and refined, yielding an improved starting point for density modification and further model-building. An approach is presented for addressing the challenge of model rebuilding after molecular replacement in cases where the placed template is very different from the structure to be determined. The approach takes advantage of the observation that a template and target structure may have local structures that can be superimposed much more closely than can their complete structures. A density-guided procedure for deformation of a properly placed template is introduced. A shift in the coordinates of each residue in the structure is calculated based on optimizing the match of model density within a 6 Å radius of the center of that residue with a prime-and-switch electron-density map. The shifts are smoothed and applied to the atoms in each residue, leading to local deformation of the template that improves the match of map and model. The model is then refined to improve the geometry and the fit of model to the structure-factor data. A new map is then calculated and the process is repeated until convergence. The procedure can extend the routine applicability of automated molecular replacement, model building and refinement to search models with over 2 Å r.m.s.d. representing 65–100% of the structure.

  10. Policy Iteration / Optimistic Policy Iteration Least-Squares Policy Iteration Experiments Least Squares Policy Iteration

    E-Print Network [OSTI]

    Scherrer, Bruno

    Policy Iteration / Optimistic Policy Iteration Least-Squares Policy Iteration Experiments Least Squares Policy Iteration Bias-Variance Trade-o in Control Problems Christophe Thiéry and Bruno Scherrer/27 #12; Policy Iteration / Optimistic Policy Iteration Least-Squares Policy Iteration Experiments Markov

  11. Statistical model based iterative reconstruction (MBIR) in clinical CT systems: Experimental assessment of noise performance

    SciTech Connect (OSTI)

    Li, Ke; Tang, Jie [Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, Wisconsin 53705 (United States)] [Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, Wisconsin 53705 (United States); Chen, Guang-Hong, E-mail: gchen7@wisc.edu [Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, Wisconsin 53705 and Department of Radiology, University of Wisconsin-Madison, 600 Highland Avenue, Madison, Wisconsin 53792 (United States)] [Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, Wisconsin 53705 and Department of Radiology, University of Wisconsin-Madison, 600 Highland Avenue, Madison, Wisconsin 53792 (United States)

    2014-04-15T23:59:59.000Z

    Purpose: To reduce radiation dose in CT imaging, the statistical model based iterative reconstruction (MBIR) method has been introduced for clinical use. Based on the principle of MBIR and its nonlinear nature, the noise performance of MBIR is expected to be different from that of the well-understood filtered backprojection (FBP) reconstruction method. The purpose of this work is to experimentally assess the unique noise characteristics of MBIR using a state-of-the-art clinical CT system. Methods: Three physical phantoms, including a water cylinder and two pediatric head phantoms, were scanned in axial scanning mode using a 64-slice CT scanner (Discovery CT750 HD, GE Healthcare, Waukesha, WI) at seven different mAs levels (5, 12.5, 25, 50, 100, 200, 300). At each mAs level, each phantom was repeatedly scanned 50 times to generate an image ensemble for noise analysis. Both the FBP method with a standard kernel and the MBIR method (Veo{sup ®}, GE Healthcare, Waukesha, WI) were used for CT image reconstruction. Three-dimensional (3D) noise power spectrum (NPS), two-dimensional (2D) NPS, and zero-dimensional NPS (noise variance) were assessed both globally and locally. Noise magnitude, noise spatial correlation, noise spatial uniformity and their dose dependence were examined for the two reconstruction methods. Results: (1) At each dose level and at each frequency, the magnitude of the NPS of MBIR was smaller than that of FBP. (2) While the shape of the NPS of FBP was dose-independent, the shape of the NPS of MBIR was strongly dose-dependent; lower dose lead to a “redder” NPS with a lower mean frequency value. (3) The noise standard deviation (?) of MBIR and dose were found to be related through a power law of ????(dose){sup ??} with the component ? ? 0.25, which violated the classical ????(dose){sup ?0.5} power law in FBP. (4) With MBIR, noise reduction was most prominent for thin image slices. (5) MBIR lead to better noise spatial uniformity when compared with FBP. (6) A composite image generated from two MBIR images acquired at two different dose levels (D1 and D2) demonstrated lower noise than that of an image acquired at a dose level of D1+D2. Conclusions: The noise characteristics of the MBIR method are significantly different from those of the FBP method. The well known tradeoff relationship between CT image noise and radiation dose has been modified by MBIR to establish a more gradual dependence of noise on dose. Additionally, some other CT noise properties that had been well understood based on the linear system theory have also been altered by MBIR. Clinical CT scan protocols that had been optimized based on the classical CT noise properties need to be carefully re-evaluated for systems equipped with MBIR in order to maximize the method's potential clinical benefits in dose reduction and/or in CT image quality improvement.

  12. Non-degenerate shell-model effective interactions from the Okamoto-Suzuki and Krenciglowa-Kuo iteration methods

    E-Print Network [OSTI]

    Huan Dong; T. T. S. Kuo; J. W. Holt

    2011-05-23T23:59:59.000Z

    We present calculations of shell-model effective interactions for both degenerate and non-degenerate model spaces using the Krenciglowa-Kuo (KK) and the extended Krenciglowa-Kuo iteration method recently developed by Okamoto, Suzuki {\\it et al.} (EKKO). The starting point is the low-momentum nucleon-nucleon interaction $V_{low-k}$ obtained from the N$^3$LO chiral two-nucleon interaction. The model spaces spanned by the $sd$ and $sdpf$ shells are both considered. With a solvable model, we show that both the KK and EKKO methods are convenient for deriving the effective interactions for non-degenerate model spaces. The EKKO method is especially desirable in this situation since the vertex function $\\hat Z$-box employed therein is well behaved while the corresponding vertex function $\\hat Q$-box employed in the Lee-Suzuki (LS) and KK methods may have singularities. The converged shell-model effective interactions given by the EKKO and KK methods are equivalent, although the former method is considerably more efficient. The degenerate $sd$-shell effective interactions given by the LS method are practically identical to those from the EKKO and KK methods. Results of the $sd$ one-shell and $sdpf$ two-shell calculations for $^{18}$O, $^{18}$F, $^{19}$O and $^{19}$F using the EKKO effective interactions are compared, and the importance of the shell-model three-nucleon forces is discussed.

  13. US ITER

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItem NotEnergy, science,SpeedingWu,IntelligenceYou are ABOUT US ITER | WHY FUSION? |

  14. Current generation by helicons and lower hybrid waves in modern tokamaks and reactors ITER and DEMO. Scenarios, modeling and antennae

    SciTech Connect (OSTI)

    Vdovin, V. L., E-mail: vdov@nfi.kiae.ru [National Research Centre 'Kurchatov Institute,' (Russian Federation)

    2013-02-15T23:59:59.000Z

    The innovative concept and 3D full-wave code modeling the off-axis current drive by radio-frequency (RF) waves in large-scale tokamaks, ITER and DEMO, for steady-state operation with high efficiency is proposed. The scheme uses the helicon radiation (fast magnetosonic waves at high (20-40) ion cyclotron frequency harmonics) at frequencies of 500-700 MHz propagating in the outer regions of the plasmas with a rotational transform. It is expected that the current generated by helicons, in conjunction with the bootstrap current, ensure the maintenance of a given value of the total current in the stability margin q(0) {>=} 2 and q(a) {>=} 4, and will help to have regimes with a negative magnetic shear and internal transport barrier to ensure stability at high normalized plasma pressure {beta}{sub N} > 3 (the so-called advanced scenarios) of interest for the commercial reactor. Modeling with full-wave three-dimensional codes PSTELION and STELEC showed flexible control of the current profile in the reactor plasmas of ITER and DEMO, using multiple frequencies, the positions of the antennae and toroidal wave slow down. Also presented are the results of simulations of current generation by helicons in the DIII-D, T-15MD, and JT-60AS tokamaks. Commercially available continuous-wave klystrons of the MW/tube range are promising for commercial stationary fusion reactors. The compact antennae of the waveguide type are proposed, and an example of a possible RF system for today's tokamaks is given. The advantages of the scheme (partially tested at lower frequencies in tokamaks) are a significant decline in the role of parametric instabilities in the plasma periphery, the use of electrically strong resonator-waveguide type antennae, and substantially greater antenna-plasma coupling.

  15. Review of recent experimental and modeling progress in the lower hybrid range of frequencies at ITER relevant parameters

    SciTech Connect (OSTI)

    Bonoli, Paul T. [Plasma Science and Fusion Center, NW16-240, MIT, Cambridge, Massachusetts 02139 (United States)

    2014-06-15T23:59:59.000Z

    Progress in experiment and simulation capability in the lower hybrid range of frequencies at ITER relevant parameters is reviewed. Use of LH power in reactor devices is motivated in terms of its potential for efficient off-axis current profile control. Recent improvements in simulation capability including the development of full-wave field solvers, inclusion of the scrape off layer (SOL) in wave propagation codes, the use of coupled ray tracing/full-wave/3D (r v{sub ?}, v{sub //}) Fokker Planck models, and the inclusion of wave scattering as well as nonlinear broadening effects in ray tracing / Fokker Planck codes are discussed. Experimental and modeling results are reviewed which are aimed at understanding the spectral gap problem in LH current drive (LHCD) and the density limit that has been observed and mitigated in LHCD experiments. Physics mechanisms that could be operative in these experiments are discussed, including toroidally induced variations in the parallel wavenumber, nonlinear broadening of the pump wave, scattering of LH waves from density fluctuations in the SOL, and spectral broadening at the plasma edge via full-wave effects.

  16. Review of recent experimental and modeling progress in the lower hybrid range of frequencies at ITER relevant parameters

    SciTech Connect (OSTI)

    Bonoli, Paul T. [Plasma Science and Fusion Center, NW16-240, MIT, Cambridge, MA 02139 (United States)

    2014-02-12T23:59:59.000Z

    Progress in experiment and simulation capability in the lower hybrid range of frequencies (LHRF) at ITER relevant parameters is reviewed. Use of LH power in reactor devices is motivated in terms of its potential for efficient off-axis current profile control. Recent improvements in simulation capability including the development of full-wave field solvers, inclusion of the scrape off layer (SOL) in wave propagation codes, the use of coupled ray tracing / full-wave / 3D (r v{sub ?}, v{sub ?}) Fokker Planck models, and the inclusion of nonlinear broadening effects in ray tracing / Fokker Planck codes are discussed. Experimental and modeling results are reviewed which are aimed at understanding the spectral gap problem in LH current drive (LHCD) and the density limit that has been observed in LHCD experiments. Physics mechanisms that could be operative in these experiments are discussed, including toroidally induced variations in the parallel wavenumber, nonlinear broadening of the pump wave, scattering of LH waves from density fluctuations in the SOL, and spectral broadening at the plasma edge via full-wave effects.

  17. A multi-scale iterative approach for finite element modeling of thermal contact resistance

    E-Print Network [OSTI]

    Thompson, Mary Kathryn, 1980-

    2007-01-01T23:59:59.000Z

    Surface topography has long been considered a key factor in the performance of many contact applications including thermal contact resistance. However, essentially all analytical and numerical models of thermal contact ...

  18. A model of lipid-free Apolipoprotein A-I revealed by iterative molecular dynamics simulation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, Xing; Lei, Dongsheng; Zhang, Lei; Rames, Matthew; Zhang, Shengli

    2015-03-20T23:59:59.000Z

    Apolipoprotein A-I (apo A-I), the major protein component of high-density lipoprotein, has been proven inversely correlated to cardiovascular risk in past decades. The lipid-free state of apo A-I is the initial stage which binds to lipids forming high-density lipoprotein. Molecular models of lipid-free apo A-I have been reported by methods like X-ray crystallography and chemical cross-linking/mass spectrometry (CCL/MS). Through structural analysis we found that those current models had limited consistency with other experimental results, such as those from hydrogen exchange with mass spectrometry. Through molecular dynamics simulations, we also found those models could not reach a stable equilibrium state. Therefore,more »by integrating various experimental results, we proposed a new structural model for lipidfree apo A-I, which contains a bundled four-helix N-terminal domain (1–192) that forms a variable hydrophobic groove and a mobile short hairpin C-terminal domain (193–243). This model exhibits an equilibrium state through molecular dynamics simulation and is consistent with most of the experimental results known from CCL/MS on lysine pairs, fluorescence resonance energy transfer and hydrogen exchange. This solution-state lipid-free apo A-I model may elucidate the possible conformational transitions of apo A-I binding with lipids in high-density lipoprotein formation.« less

  19. Adaptive Density Estimation in the Pile-up Model Involving Measurement Errors

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Adaptive Density Estimation in the Pile-up Model Involving Measurement Errors Fabienne Comte, Tabea of nonparametric density estimation in the pile-up model. Adaptive nonparametric estimators are proposed for the pile-up model in its simple form as well as in the case of additional measurement errors. Furthermore

  20. Automated main-chain model building by template matching and iterative fragment extension

    SciTech Connect (OSTI)

    Terwilliger, Thomas C., E-mail: terwilliger@lanl.gov [Mail Stop M888, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2003-01-01T23:59:59.000Z

    A method for automated macromolecular main-chain model building is described. An algorithm for the automated macromolecular model building of polypeptide backbones is described. The procedure is hierarchical. In the initial stages, many overlapping polypeptide fragments are built. In subsequent stages, the fragments are extended and then connected. Identification of the locations of helical and ?-strand regions is carried out by FFT-based template matching. Fragment libraries of helices and ?-strands from refined protein structures are then positioned at the potential locations of helices and strands and the longest segments that fit the electron-density map are chosen. The helices and strands are then extended using fragment libraries consisting of sequences three amino acids long derived from refined protein structures. The resulting segments of polypeptide chain are then connected by choosing those which overlap at two or more C{sup ?} positions. The fully automated procedure has been implemented in RESOLVE and is capable of model building at resolutions as low as 3.5 Å. The algorithm is useful for building a preliminary main-chain model that can serve as a basis for refinement and side-chain addition.

  1. US ITER Moving Forward

    ScienceCinema (OSTI)

    US ITER / ORNL

    2012-03-16T23:59:59.000Z

    US ITER Project Manager Ned Sauthoff, joined by Wayne Reiersen, Team Leader Magnet Systems, and Jan Berry, Team Leader Tokamak Cooling System, discuss the U.S.'s role in the ITER international collaboration.

  2. On the Logic of Iterated Non-prioritised Richard Booth

    E-Print Network [OSTI]

    Booth, Richard

    , and of iterated revision [3, 5, 7, 8, 17, 21], i.e., the study of the behaviour of an agent's beliefs underOn the Logic of Iterated Non-prioritised Revision Richard Booth Department of Computer Science. We look at iterated non-prioritised belief revision, using as a starting point a model of non

  3. On the Strategy and Requirements for Neutronics Testing in ITER

    SciTech Connect (OSTI)

    Youssef, M.Z. [University of California-Los Angeles (United States); Sawan, M.E. [University of Wisconsin-Madison (United States)

    2005-05-15T23:59:59.000Z

    Neutronics testing is among the several types of fusion technology testing scheduled to be performed in ITER. The three ports assigned for testing will test several blanket concepts proposed by the various parties with test blanket modules (TBM) that utilize different breeders and coolants. Nevertheless, neutronics issues to be resolved in ITER-TBM are generic in nature and are important to each TBM type. Dedicated neutronics tests specifically address the accuracy involved in predicting key neutronics parameters such as tritium production rate, TPR, volumetric heating rate, induced activation and decay heat, and radiation damage to the reactor components. In this paper, we address some strategies for performing the neutronics tests. Tritium self-sufficiency cannot be confirmed by testing in ITER, however, the testing can provide valuable information regarding the main parameters needed to assess the feasibility of achieving tritium self-sufficiency. The paper also addresses the operational requirement (i.e. flux and fluence) as well as the geometrical requirement of the test module (i.e. minimum size) in order to have meaningful and useful tests. Measured neutronics data require high spatial resolution. This necessitates that the measured quantity be as flat as possible in the innermost locations inside the test module. This requirement has been confirmed in the present work based on results from two-dimensional calculations. The US and Japan solid breeder test blanket modules are placed inside half a port in ITER. The R-{theta} model used accounts for the presence of the ITER shielding blanket and the surrounding frame of the port.

  4. Iterative Solution of Maxwell's Equations for an Induction Motor

    E-Print Network [OSTI]

    Shayak Bhattacharjee

    2014-07-29T23:59:59.000Z

    In this work we use classical electromagnetism to analyse a three-phase induction motor. We first cast the motor as a boundary value problem involving two phenomenological time-constants. These are derived from the widely used equivalent circuit model of the induction motor. We then use an iterative procedure to evaluate these constants and obtain the motor performance equations. Our results depend only on the geometrical parameters of the motor and can be used to derive precise expressions for the excitation frequency and applied voltage needed to extract maximum performance from a given motor at any rotation speed.

  5. Current generation by helicons and LH waves in modern tokamaks and reactors FNSF-AT, ITER and DEMO. Scenarios, modeling and antennae

    SciTech Connect (OSTI)

    Vdovin, V. [NRC Kurchatov Institute Tokamak Physics Institute, Moscow (Russian Federation)

    2014-02-12T23:59:59.000Z

    The Innovative concept and 3D full wave code modeling Off-axis current drive by RF waves in large scale tokamaks, reactors FNSF-AT, ITER and DEMO for steady state operation with high efficiency was proposed [1] to overcome problems well known for LH method [2]. The scheme uses the helicons radiation (fast magnetosonic waves at high (20–40) IC frequency harmonics) at frequencies of 500–1000 MHz, propagating in the outer regions of the plasmas with a rotational transform. It is expected that the current generated by Helicons will help to have regimes with negative magnetic shear and internal transport barrier to ensure stability at high normalized plasma pressure ?{sub N} > 3 (the so-called Advanced scenarios) of interest for FNSF and the commercial reactor. Modeling with full wave three-dimensional codes PSTELION and STELEC2 showed flexible control of the current profile in the reactor plasmas of ITER, FNSF-AT and DEMO [2,3], using multiple frequencies, the positions of the antennae and toroidal waves slow down. Also presented are the results of simulations of current generation by helicons in tokamaks DIII-D, T-15MD and JT-60SA [3]. In DEMO and Power Plant antenna is strongly simplified, being some analoge of mirrors based ECRF launcher, as will be shown. For spherical tokamaks the Helicons excitation scheme does not provide efficient Off-axis CD profile flexibility due to strong coupling of helicons with O-mode, also through the boundary conditions in low aspect machines, and intrinsic large amount of trapped electrons, as is shown by STELION modeling for the NSTX tokamak. Brief history of Helicons experimental and modeling exploration in straight plasmas, tokamaks and tokamak based fusion Reactors projects is given, including planned joint DIII-D – Kurchatov Institute experiment on helicons CD [1].

  6. ITER MHD stability analysis. Final report

    SciTech Connect (OSTI)

    Turnbull, A.D.

    1996-05-01T23:59:59.000Z

    This report summarizes the final results and conclusions from work done for ITER under the DOE Task 18 (Raytheon Task ITER-GA 4002E). The work was performed in collaboration with D. Pearlstein and R. Bulmer of the Lawrence Livermore National Laboratory (LLNL), in close conjunction with D. Boucher of the ITER Joint Central Team (JCT). The work was partly done at General Atomics in San Diego and partly at LLNL. Approximately eight hours per week were spent from August 1994 through June 1995, with a no-cost extension through December 1995. The report covers work on the ideal MHD stability analysis for the ITER TAC scenarios and DIII-D ITER Demonstration Discharges, code modifications performed in order to efficiently and accurately complete the stability calculations, and additional collaborative efforts involving code benchmarking and dissemination of the DIII-D ITER Demonstration Discharge data. The work spawned several presentations and reports, including significant contributions to published IAEA Proceedings, and these are also summarized. 8 refs., 9 figs.

  7. Use of the iterative solution method for coupled finite element and boundary element modeling; Yucca Mountain Site Characterization Project

    SciTech Connect (OSTI)

    Koteras, J.R.

    1993-07-01T23:59:59.000Z

    Tunnels buried deep within the earth constitute an important class geomechanics problems. Two numerical techniques used for the analysis of geomechanics problems, the finite element method and the boundary element method, have complementary characteristics for applications to problems of this type. The usefulness of combining these two methods for use as a geomechanics analysis tool has been recognized for some time, and a number of coupling techniques have been proposed. However, not all of them lend themselves to efficient computational implementations for large-scale problems. This report examines a coupling technique that can form the basis for an efficient analysis tool for large scale geomechanics problems through the use of an iterative equation solver.

  8. Pore scale modeling of reactive transport involved in geologic CO2 sequestration

    SciTech Connect (OSTI)

    Kang, Qinjin [Los Alamos National Laboratory; Lichtner, Peter C [Los Alamos National Laboratory; Viswanathan, Hari S [Los Alamos National Laboratory; Abdel-fattah, Amr I [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    We apply a multi-component reactive transport lattice Boltzmann model developed in previolls studies to modeling the injection of a C02 saturated brine into various porous media structures at temperature T=25 and 80 C. The porous media are originally consisted of calcite. A chemical system consisting of Na+, Ca2+, Mg2+, H+, CO2(aq), and CI-is considered. The fluid flow, advection and diHusion of aqueous species, homogeneous reactions occurring in the bulk fluid, as weB as the dissolution of calcite and precipitation of dolomite are simulated at the pore scale. The effects of porous media structure on reactive transport are investigated. The results are compared with continuum scale modeling and the agreement and discrepancy are discussed. This work may shed some light on the fundamental physics occurring at the pore scale for reactive transport involved in geologic C02 sequestration.

  9. Status of ITER Negotiations Warren Marton

    E-Print Network [OSTI]

    for decommissioning. · ITER parties met in Barcelona, Feb. 7-11, to complete the technical level negotiations construction, & costs for operation, deactivation, and decommissioning required much interaction with all · Last issue is the complicated matter of P&I and waiver thereto, involving French Nuclear Safety

  10. ITER convertible blanket evaluation

    SciTech Connect (OSTI)

    Wong, C.P.C.; Cheng, E.

    1995-09-01T23:59:59.000Z

    Proposed International Thermonuclear Experimental Reactor (ITER) convertible blankets were reviewed. Key design difficulties were identified. A new particle filter concept is introduced and key performance parameters estimated. Results show that this particle filter concept can satisfy all of the convertible blanket design requirements except the generic issue of Be blanket lifetime. If the convertible blanket is an acceptable approach for ITER operation, this particle filter option should be a strong candidate.

  11. The second iteration of the Systems Prioritization Method: A systems prioritization and decision-aiding tool for the Waste Isolation Pilot Plant: Volume 2, Summary of technical input and model implementation

    SciTech Connect (OSTI)

    Prindle, N.H.; Mendenhall, F.T.; Trauth, K.; Boak, D.M. [Sandia National Labs., Albuquerque, NM (United States); Beyeler, W. [Science Applications International Corp., Albuquerque, NM (United States); Hora, S. [Hawaii Univ., Hilo, HI (United States); Rudeen, D. [New Mexico Engineering Research Inst., Albuquerque, NM (United States)

    1996-05-01T23:59:59.000Z

    The Systems Prioritization Method (SPM) is a decision-aiding tool developed by Sandia National Laboratories (SNL). SPM provides an analytical basis for supporting programmatic decisions for the Waste Isolation Pilot Plant (WIPP) to meet selected portions of the applicable US EPA long-term performance regulations. The first iteration of SPM (SPM-1), the prototype for SPM< was completed in 1994. It served as a benchmark and a test bed for developing the tools needed for the second iteration of SPM (SPM-2). SPM-2, completed in 1995, is intended for programmatic decision making. This is Volume II of the three-volume final report of the second iteration of the SPM. It describes the technical input and model implementation for SPM-2, and presents the SPM-2 technical baseline and the activities, activity outcomes, outcome probabilities, and the input parameters for SPM-2 analysis.

  12. Plans for US Contributions to ITER U.S. ITER Plans for US Contributions to ITER

    E-Print Network [OSTI]

    windings 75% cooling for divertor, vacuum vessel, ... 20% blanket/shield pellet injector tokamak exhaust supplies #12;Plans for US Contributions to ITER U.S. ITER Plans for US Contributions to ITER December 4 Exploring: - Seam-less tube conduit - Perforated central cooling tube #12;Plans for US Contributions to ITER

  13. Nuclear Forensic Inferences Using Iterative Multidimensional Statistics

    SciTech Connect (OSTI)

    Robel, M; Kristo, M J; Heller, M A

    2009-06-09T23:59:59.000Z

    Nuclear forensics involves the analysis of interdicted nuclear material for specific material characteristics (referred to as 'signatures') that imply specific geographical locations, production processes, culprit intentions, etc. Predictive signatures rely on expert knowledge of physics, chemistry, and engineering to develop inferences from these material characteristics. Comparative signatures, on the other hand, rely on comparison of the material characteristics of the interdicted sample (the 'questioned sample' in FBI parlance) with those of a set of known samples. In the ideal case, the set of known samples would be a comprehensive nuclear forensics database, a database which does not currently exist. In fact, our ability to analyze interdicted samples and produce an extensive list of precise materials characteristics far exceeds our ability to interpret the results. Therefore, as we seek to develop the extensive databases necessary for nuclear forensics, we must also develop the methods necessary to produce the necessary inferences from comparison of our analytical results with these large, multidimensional sets of data. In the work reported here, we used a large, multidimensional dataset of results from quality control analyses of uranium ore concentrate (UOC, sometimes called 'yellowcake'). We have found that traditional multidimensional techniques, such as principal components analysis (PCA), are especially useful for understanding such datasets and drawing relevant conclusions. In particular, we have developed an iterative partial least squares-discriminant analysis (PLS-DA) procedure that has proven especially adept at identifying the production location of unknown UOC samples. By removing classes which fell far outside the initial decision boundary, and then rebuilding the PLS-DA model, we have consistently produced better and more definitive attributions than with a single pass classification approach. Performance of the iterative PLS-DA method compared favorably to that of classification and regression tree (CART) and k nearest neighbor (KNN) algorithms, with the best combination of accuracy and robustness, as tested by classifying samples measured independently in our laboratories against the vendor QC based reference set.

  14. Mechanochemical modeling of dynamic microtubule growth involving sheet-to-tube transition

    E-Print Network [OSTI]

    Xiang-Ying Ji; Xi-Qiao Feng

    2011-08-02T23:59:59.000Z

    Microtubule dynamics is largely influenced by nucleotide hydrolysis and the resultant tubulin configuration changes. The GTP cap model has been proposed to interpret the stabilizing mechanism of microtubule growth from the view of hydrolysis effects. Besides, the microtubule growth involves the closure of a curved sheet at its growing end. The curvature conversion also helps to stabilize the successive growth, and the curved sheet is referred to as the conformational cap. However, there still lacks theoretical investigation on the mechanical-chemical coupling growth process of microtubules. In this paper, we study the growth mechanisms of microtubules by using a coarse-grained molecular method. Firstly, the closure process involving a sheet-to-tube transition is simulated. The results verify the stabilizing effect of the sheet structure, and the minimum conformational cap length that can stabilize the growth is demonstrated to be two dimers. Then, we show that the conformational cap can function independently of the GTP cap, signifying the pivotal role of mechanical factors. Furthermore, based on our theoretical results, we describe a Tetris-like growth style of microtubules: the stochastic tubulin assembly is regulated by energy and harmonized with the seam zipping such that the sheet keeps a practically constant length during growth.

  15. US ITER | Media Corner

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin TransitionProgram |Frank Casella US ITER QualityKelliUS ITER Major

  16. US ITER | Media Corner

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin TransitionProgram |Frank Casella US ITER QualityKelliUS ITER

  17. EU signs ITER deal Negotiations on the ITER international nuclear

    E-Print Network [OSTI]

    Korea and the US, the agreement aims to develop a project that will test the feasibility of nuclearEU signs ITER deal Negotiations on the ITER international nuclear fusion project have been on Wednesday reached a final agreement on the ITER project after years of talks. "The completion

  18. ITER Fusion Energy

    ScienceCinema (OSTI)

    Dr. Norbert Holtkamp

    2010-01-08T23:59:59.000Z

    ITER (in Latin ?the way?) is designed to demonstrate the scientific and technological feasibility of fusion energy. Fusion is the process by which two light atomic nuclei combine to form a heavier over one and thus release energy. In the fusion process two isotopes of hydrogen ? deuterium and tritium ? fuse together to form a helium atom and a neutron. Thus fusion could provide large scale energy production without greenhouse effects; essentially limitless fuel would be available all over the world. The principal goals of ITER are to generate 500 megawatts of fusion power for periods of 300 to 500 seconds with a fusion power multiplication factor, Q, of at least 10. Q ? 10 (input power 50 MW / output power 500 MW). The ITER Organization was officially established in Cadarache, France, on 24 October 2007. The seven members engaged in the project ? China, the European Union, India, Japan, Korea, Russia and the United States ? represent more than half the world?s population. The costs for ITER are shared by the seven members. The cost for the construction will be approximately 5.5 billion Euros, a similar amount is foreseen for the twenty-year phase of operation and the subsequent decommissioning.

  19. Regions of influence for two iterative methods 

    E-Print Network [OSTI]

    Leifeste, Arlee Ross

    1966-01-01T23:59:59.000Z

    Subject Mathematics REGIONS OF INFLUENCE FOR TWO ITERATIVE METHODS A Thesis By ARLEE ROSS LEIFESTE Approved as to style and content by: (Chairman of Committee) (Head of Department) (Member) (N b )' January 1966 ACKNOWLEDGMENT The author wishes... purpose of the present discussion is to initiate a study of the "regions of influence" of the various solutions of the simul- taneous equations involved. Let the simultaneous functions be denoted and let ( y , y , , y 1 be a point of n...

  20. Regional groundwater modeling of the saturated zone in the vicinity of Yucca Mountain, Nevada; Iterative Performance Assessment, Phase 2

    SciTech Connect (OSTI)

    Ahola, M.; Sagar, B. [Southwest Research Inst., San Antonio, TX (United States). Center for Nuclear Waste Regulatory Analyses

    1992-10-01T23:59:59.000Z

    Results of groundwater modeling of the saturated zone in the vicinity of Yucca Mountain are presented. Both a regional (200 {times} 200 km) and subregional (50 {times} 50 km) model were used in the analyses. Simulations were conducted to determine the impact of various disruptive that might take place over the life span of a proposed Yucca Mountain geologic conditions repository on the groundwater flow field, as well as changes in the water-table elevations. These conditions included increases in precipitation and groundwater recharge within the regional model, changes in permeability of existing hydrogeologic barriers, a:nd the vertical intrusion of volcanic dikes at various orientations through the saturated zone. Based on the regional analysis, the rise in the water-table under Yucca Mountain due to various postulated conditions ranged from only a few meters to 275 meters. Results of the subregional model analysis, which was used to simulate intrusive dikes approximately 4 kilometers in length in the vicinity of Yucca Mountain, showed water-table rises ranging from a few meters to as much as 103 meters. Dikes oriented approximately north-south beneath Yucca Mountain produced the highest water-table rises. The conclusions drawn from this analysis are likely to change as more site-specific data become available and as the assumptions in the model are improved.

  1. The Pugh Controlled Convergence Method: Model-Based Evaluation and Implications for Design Theory

    E-Print Network [OSTI]

    Wijnia, Ype

    This paper evaluates the Pugh Controlled Convergence method and its relationship to recent developments in design theory. Computer executable models are proposed simulating a team of people involved in iterated cycles of ...

  2. ITER breeding blanket design

    SciTech Connect (OSTI)

    Gohar, Y.; Cardella, A.; Ioki, K.; Lousteau, D.; Mohri, K.; Raffray, R.; Zolti, E. [ITER Joint Central Team, Garching (Germany)] [and others

    1995-12-31T23:59:59.000Z

    A breeding blanket design has been developed for ITER to provide the necessary tritium fuel to achieve the technical objectives of the Enhanced Performance Phase. It uses a ceramic breeder and water coolant for compatibility with the ITER machine design of the Basic Performance Phase. Lithium zirconate and lithium oxide am the selected ceramic breeders based on the current data base. Enriched lithium and beryllium neutron multiplier are used for both breeders. Both forms of beryllium material, blocks and pebbles are used at different blanket locations based on thermo-mechanical considerations and beryllium thickness requirements. Type 316LN austenitic steel is used as structural material similar to the shielding blanket. Design issues and required R&D data are identified during the development of the design.

  3. ITER blanket designs

    SciTech Connect (OSTI)

    Gohar, J.; Parker, R.; Rebut, P.H. [ITER Garching Joint Work Site, Garching bei Munchen (Germany)

    1994-12-31T23:59:59.000Z

    The ITER first wall, blanket, and shield system is being designed to handle 1.5{plus_minus}0.3 GW of fusion power and 3 MWa/m{sup 2} average neutron fluence. The reference shielding blanket (non breeding) uses austenitic steel structural material and water coolant with a copper first wall coated with beryllium. The first wall is protected by beryllium bumper limiters. The choice of copper first wall is dictated by the surface heat flux values anticipated during ITER operation. The water coolant is used at low pressure and low temperature. Liquid lithium is used as tritium breeder and coolant to alleviate issues of coolant breeder compatibility and reactivity. A layer of beryllium is incorporated in the blanket to improve the shielding performance and to insure tritium self-sufficiency. In addition, a shielding zone is incorporated at the back of the blanket to allow rewelding the vacuum vessel material during the ITER lifetime. The lithium coolant velocity required to remove the nuclear heating and the surface heat flux is 2 m/s, which produces a pressure drop of 0.6 MPa. Vanadium alloy (V-5Cr-5Ti) is being considered as the structural material because it can accommodate high heat loads and has good mechanical properties at high temperatures, high neutron fluence capability, low degradation under irradiation, good compatibility with liquid lithium, low decay heat, low waste disposal rating, and adequate strength to accommodate the electromagnetic loads during plasma disruption events.

  4. Neutron cameras for ITER

    SciTech Connect (OSTI)

    Johnson, L.C.; Barnes, C.W.; Batistoni, P. [ITER San Diego Joint Work Site, La Jolla, CA (United States)] [and others

    1998-12-31T23:59:59.000Z

    Neutron cameras with horizontal and vertical views have been designed for ITER, based on systems used on JET and TFTR. The cameras consist of fan-shaped arrays of collimated flight tubes, with suitably chosen detectors situated outside the biological shield. The sight lines view the ITER plasma through slots in the shield blanket and penetrate the vacuum vessel, cryostat, and biological shield through stainless steel windows. This paper analyzes the expected performance of several neutron camera arrangements for ITER. In addition to the reference designs, the authors examine proposed compact cameras, in which neutron fluxes are inferred from {sup 16}N decay gammas in dedicated flowing water loops, and conventional cameras with fewer sight lines and more limited fields of view than in the reference designs. It is shown that the spatial sampling provided by the reference designs is sufficient to satisfy target measurement requirements and that some reduction in field of view may be permissible. The accuracy of measurements with {sup 16}N-based compact cameras is not yet established, and they fail to satisfy requirements for parameter range and time resolution by large margins.

  5. Report of panel 1: The appropriate scope and mission of ITER

    SciTech Connect (OSTI)

    Linford, R.K. (Los Alamos National Lab., NM (United States)); Weitzner, H.; Abdou, M.A.; Baldwin, D.E.; Berkner, K.H.; Berry, L.A.; Culler, F.L.; Dean, S.O.; DeFreece, D.A.; Gauster, W.B. (and others)

    1992-12-01T23:59:59.000Z

    This panel looked at the mission of ITER, and how the US should address the present plans, and considers a number of alternative plans to arrive at the eventual goals of ITER. The panel considered three major approaches which have been discussed on the international scale, and tries to present the strengths, weaknesses, and possible changes to these plans. It suggests that any of these plans can arrive at the eventual aim, but may involve differing risks and time commitments. All plans involve ITER design studies, development work on technologies which must be in place for ITER design to succeed, and testing of materials and components for application in the device.

  6. SciDAC Center for Simulation of Wave-Plasma Interactions - Iterated Finite-Orbit Monte Carlo Simulations with Full-Wave Fields for Modeling Tokamak ICRF Wave Heating Experiments - Final Report

    SciTech Connect (OSTI)

    Choi, Myunghee [Retired] [Retired; Chan, Vincent S. [General Atomics] [General Atomics

    2014-02-28T23:59:59.000Z

    This final report describes the work performed under U.S. Department of Energy Cooperative Agreement DE-FC02-08ER54954 for the period April 1, 2011 through March 31, 2013. The goal of this project was to perform iterated finite-orbit Monte Carlo simulations with full-wall fields for modeling tokamak ICRF wave heating experiments. In year 1, the finite-orbit Monte-Carlo code ORBIT-RF and its iteration algorithms with the full-wave code AORSA were improved to enable systematical study of the factors responsible for the discrepancy in the simulated and the measured fast-ion FIDA signals in the DIII-D and NSTX ICRF fast-wave (FW) experiments. In year 2, ORBIT-RF was coupled to the TORIC full-wave code for a comparative study of ORBIT-RF/TORIC and ORBIT-RF/AORSA results in FW experiments.

  7. Evolution of Deixis: Personal Pronouns in an Iterated Learning Experiment 

    E-Print Network [OSTI]

    Komorowska, Krystyna

    2012-11-28T23:59:59.000Z

    To date, empirical research on language evolution has been based on entirely non-deictic languages. This study presents an experiment using the Iterated Learning Model to establish in what way deixis may affect process of language transmission...

  8. Benchmarking ICRF simulations for ITER

    SciTech Connect (OSTI)

    R. V. Budny, L. Berry, R. Bilato, P. Bonoli, M. Brambilla, R.J. Dumont, A. Fukuyama, R. Harvey, E.F. Jaeger, E. Lerche, C.K. Phillips, V. Vdovin, J. Wright, and members of the ITPA-IOS

    2010-09-28T23:59:59.000Z

    Abstract Benchmarking of full-wave solvers for ICRF simulations is performed using plasma profiles and equilibria obtained from integrated self-consistent modeling predictions of four ITER plasmas. One is for a high performance baseline (5.3 T, 15 MA) DT H-mode plasma. The others are for half-field, half-current plasmas of interest for the pre-activation phase with bulk plasma ion species being either hydrogen or He4. The predicted profiles are used by seven groups to predict the ICRF electromagnetic fields and heating profiles. Approximate agreement is achieved for the predicted heating power partitions for the DT and He4 cases. Profiles of the heating powers and electromagnetic fields are compared.

  9. Iterated integrals of superconnections

    E-Print Network [OSTI]

    Igusa, Kiyoshi

    2009-01-01T23:59:59.000Z

    Starting with a Z-graded superconnection on a graded vector bundle over a smooth manifold M, we show how Chen's iterated integration of such a superconnection over smooth simplices in M gives an A-infinity functor if and only if the superconnection is flat. If the graded bundle is trivial, this gives a twisting cochain. Very similar results were obtained by K.T. Chen using similar methods. This paper is intended to explain this from scratch beginning with the definition and basic properties of a connection and ending with an exposition of Chen's "formal connections" and a brief discussion of how this is related to higher Reidemeister torsion.

  10. US ITER | About

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin TransitionProgram | Departmentcontributes 75%TokamakITER Magnet

  11. US ITER | About

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin TransitionProgram | Departmentcontributes 75%TokamakITER

  12. US ITER | Jobs

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin TransitionProgram |Frank Casella US ITER Quality Assurance,

  13. US ITER | Jobs

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin TransitionProgram |Frank Casella US ITER Quality Assurance,Kevin

  14. US ITER | Jobs

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin TransitionProgram |Frank Casella US ITER Quality

  15. US ITER | Jobs

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin TransitionProgram |Frank Casella US ITER QualityKelli Kizer

  16. US ITER | Jobs

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin TransitionProgram |Frank Casella US ITER QualityKelli KizerNicolai

  17. US ITER | Media Corner

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin TransitionProgram |Frank Casella US ITER QualityKelli

  18. US ITER | Media Corner

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin TransitionProgram |Frank Casella US ITER QualityKelliUS ITERtest

  19. US ITER | Media Corner

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin TransitionProgram |Frank Casella US ITER QualityKelliUS ITERtestNew

  20. US ITER | Media Corner

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin TransitionProgram |Frank Casella US ITER QualityKelliUS

  1. US ITER | Media Corner

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin TransitionProgram |Frank Casella US ITER QualityKelliUSLife-size

  2. US ITER | Media Corner

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin TransitionProgram |Frank Casella US ITER

  3. What is ITER

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening aTurbulenceUtilizeRuraltheWelcome NationalEngineerWhat is ITER?

  4. US ITER | Jobs

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItemResearch >Internship Program TheSite Map Site Map HomeUS Key Contact KeyUS ITER

  5. US ITER | About

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening aTurbulence may bedieselsummer gasoline price0US FusionprimeITER

  6. US ITER | Media Corner

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening aTurbulence may bedieselsummerFact Sheets Fact Sheets The ITER

  7. US ITER | Media Corner

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening aTurbulence may bedieselsummerFact Sheets Fact Sheets The ITER3D

  8. US ITER | Media Corner

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening aTurbulence may bedieselsummerFact Sheets Fact Sheets TheITER's

  9. US ITER | Media Corner

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening aTurbulence may bedieselsummerFact Sheets Fact SheetsUS ITER preps

  10. US ITER | Media Corner

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  11. US ITER | Media Corner

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening aTurbulence may bedieselsummerFact Sheets FactUSUS ITER ships

  12. US ITER | Media Corner

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening aTurbulence may bedieselsummerFact Sheets FactUSUS ITER

  13. US ITER | Media Corner

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  14. US ITER | Media Corner

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening aTurbulence may bedieselsummerFact Sheets FactUSUS ITER6 News7

  15. US ITER | Media Corner

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  16. US ITER | Media Corner

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  17. US ITER | Media Corner

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  18. What is ITER

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsing Maps1DOETHEWeeklyTRUDoesmo·men·tumSciTechinITER?

  19. US ITER Project Providing a Facility for

    E-Print Network [OSTI]

    US ITER Project Providing a Facility for Burning Plasma Research Ned Sauthoff Project Manager, US to position the US for Burning Plasma Research #12;U.S. ITER / Sauthoff Slide 2 Structure of the Talk... ITER

  20. Department of Energy ITER Project

    E-Print Network [OSTI]

    of operation to meet demand, and manageable waste. Currently, the ITER project is at the stage where the final responsible for procurements of in-kind hardware in its own territory with its own currency, a direct) for the base estimate consisting of about $4 billion for ITER hardware, initial spares, buildings

  1. Contents of ITER deal revealed The Yomiuri Shimbun (May 27, 2005, 4 am)

    E-Print Network [OSTI]

    in thermonuclear fusion. The country also will supply 20 percent of workers to ITER facilities. The four other on the roles of host and non-hosting countries involved in the International Thermonuclear Experimental Reactor. The planned ITER is an experimental facility for a thermonuclear reactor designed to produce power by fusing

  2. ELM heat flux in the ITER divertor

    SciTech Connect (OSTI)

    Leonard, A.W.; Osborne, T.H. [General Atomics, San Diego, CA (United States); Hermann, A.; Suttrop, W. [Max Planck Inst. fuer Plasmaphysics (Germany); Itami, K. [Japan Atomic Energy Research Inst. (Japan); Lingertat, J. [JET Joint Undertaking, Abingdon (United Kingdom); Loarte, A. [Next European Torus, Garching (Germany)

    1998-07-01T23:59:59.000Z

    Edge-Localized-Modes (ELMs) have the potential to produce unacceptable levels of erosion of the ITER divertor. Ablation of the carbon divertor target will occur if the surface temperature rises above about 2,500 C. Because a large number of ELMs, {ge}1000, are expected in each discharge it is important that the surface temperature rise due to an individual ELM remain below this threshold. Calculations that have been carried out for the ITER carbon divertor target indicate ablation will occur for ELM energy {ge}0.5MJ/m{sup 2} if it is deposited in 0.1 ms, or 1.2 MJ/m{sup 2} if the deposition time is 1.0 ms. Since {Delta}T{proportional_to}Q{Delta}t{sup {minus}1/2}, an ablation threshold can be estimated at Q{Delta}t{sup {minus}1/2}{approx}45 MJm{sup {minus}2} s{sup {minus}1/2} where Q is the divertor ELM energy density in J-m{sup {minus}2} and {Delta}t is the time in seconds for that deposition. If a significant fraction of ELMs exceed this threshold then an unacceptable level of erosion may take place. The ablation parameter in ITER can be determined by scaling four factors from present experiments: the ELM energy loss from the core plasma, the fraction of ELM energy deposited on the divertor target, the area of the ELM profile onto the target, and the time for the ELM deposition. ELM data from JET, ASDEX-Upgrade, JT-60U, DIII-D and Compass-D have been assembled by the ITER Divertor Modeling and Database expert group into a database for the purpose of predicting these factors for ELMs in the ITER divertor.

  3. U.S. Plans and Strategy for ITER Blanket Testing

    SciTech Connect (OSTI)

    Abdou, M. [UCLA Fusion Engineering Sciences (United States); Sze, D. [UCSD Advanced Energy Technology Group (United States); Wong, C. [General Atomics (United States); Sawan, M. [University of Wisconsin Fusion Technology Institute, Madison (United States); Ying, A. [UCLA Fusion Engineering Sciences (United States); Morley, N.B. [UCLA Fusion Engineering Sciences (United States); Malang, S

    2005-04-15T23:59:59.000Z

    Testing blanket concepts in the integrated fusion environment is one of the principal objectives of ITER. Blanket test modules will be inserted in ITER from Day 1 of its operation and will provide the first experimental data on the feasibility of the D-T cycle for fusion. With the US rejoining ITER, the US community has decided to have strong participation in the ITER Test Blanket Module (TBM) Program. A US strategy for ITER-TBM has evolved that emphasizes international collaboration. A study was initiated to select the two blanket options for the US ITER-TBM in light of new R and D results from the US and world programs over the past decade. The study is led by the Plasma Chamber community in partnership with the Materials, PFC, Safety, and physics communities. The study focuses on assessment of the critical feasibility issues for candidate blanket concepts and it is strongly coupled to R and D of modeling and experiments. Examples of issues are MHD insulators, SiC insert viability and compatibility with PbLi, tritium permeation, MHD effects on heat transfer, solid breeder 'temperature window' and thermomechanics, and chemistry control of molten salts. A dual coolant liquid breeder and a helium-cooled solid breeder blanket concept have been selected for the US ITER-TBM.

  4. Iterative Decoding and Turbo Equalization: The Z-Crease Phenomenon

    E-Print Network [OSTI]

    Jing Li; Kai Xie

    2013-06-03T23:59:59.000Z

    Iterative probabilistic inference, popularly dubbed the soft-iterative paradigm, has found great use in a wide range of communication applications, including turbo decoding and turbo equalization. The classic approach of analyzing the iterative approach inevitably use the statistical and information-theoretical tools that bear ensemble-average flavors. This paper consider the per-block error rate performance, and analyzes it using nonlinear dynamical theory. By modeling the iterative processor as a nonlinear dynamical system, we report a universal "Z-crease phenomenon:" the zig-zag or up-and-down fluctuation -- rather than the monotonic decrease -- of the per-block errors, as the number of iteration increases. Using the turbo decoder as an example, we also report several interesting motion phenomenons which were not previously reported, and which appear to correspond well with the notion of "pseudo codewords" and "stopping/trapping sets." We further propose a heuristic stopping criterion to control Z-crease and identify the best iteration. Our stopping criterion is most useful for controlling the worst-case per-block errors, and helps to significantly reduce the average-iteration numbers.

  5. Fusion project decision delayed ITER -NUCLEAR FUSION PROJECT

    E-Print Network [OSTI]

    -free energy - but the reactor will take 10 years to build. Pros and cons Member countries of the International research facility and a more moderate climate. Iter consortium European Union United States Russia China the decision is highly political, involving huge amounts of horse-trading behind the scenes. Delegates were

  6. Demonstration of ITER Operational Scenarios on DIII-D

    SciTech Connect (OSTI)

    Doyle, E J; Budny, R V; DeBoo, J C; Ferron, J R; Jackson, G L; Luce, T C; Murakami, M; Osborne, T H; Park, J; Politzer, P A; Reimerdes, H; Casper, T A; Challis, C D; Groebner, R J; Holcomb, C T; Hyatt, A W; La Haye, R J; McKee, G R; Petrie, T W; Petty, C C; Rhodes, T L; Shafer, M W; Snyder, P B; Strait, E J; Wade, M R; Wang, G; West, W P; Zeng, L

    2008-10-13T23:59:59.000Z

    The DIII-D program has recently initiated an effort to provide suitably scaled experimental evaluations of four primary ITER operational scenarios. New and unique features of this work are that the plasmas incorporate essential features of the ITER scenarios and anticipated operating characteristics; e.g., the plasma cross-section, aspect ratio and value of I/aB of the DIII-D discharges match the ITER design, with size reduced by a factor of 3.7. Key aspects of all four scenarios, such as target values for {beta}{sub N} and H{sub 98}, have been replicated successfully on DIII-D, providing an improved and unified physics basis for transport and stability modeling, as well as for performance extrapolation to ITER. In all four scenarios normalized performance equals or closely approaches that required to realize the physics and technology goals of ITER, and projections of the DIII-D discharges are consistent with ITER achieving its goals of {ge} 400 MW of fusion power production and Q {ge} 10. These studies also address many of the key physics issues related to the ITER design, including the L-H transition power threshold, the size of ELMs, pedestal parameter scaling, the impact of tearing modes on confinement and disruptivity, beta limits and the required capabilities of the plasma control system. An example of direct influence on the ITER design from this work is a modification of the specified operating range in internal inductance at 15 MA for the poloidal field coil set, based on observations that the measured inductance in the baseline scenario case lay outside the original ITER specification.

  7. Optical model potentials involving loosely bound p-shell nuclei around 10 MeV/nucleon 

    E-Print Network [OSTI]

    Trache, L.; Azhari, A.; Clark, HL; Gagliardi, Carl A.; Lui, YW; Mukhamedzhanov, AM; Tribble, Robert E.; Carstoiu, F.

    2000-01-01T23:59:59.000Z

    model with real effective interactions the absorption is accounted for phenomenologically by adding an imaginary potential of the same shape as the real part U~r !5~NV1iNW!V fold~r !, ~15! whereas for the cases when the effective interaction also... reanalyzed all our elastic scattering data using double folding potentials obtained with the six effective interactions outlined above. The renormalization constants NV and NW were further adjusted to fit the elastic scattering data using Eq. ~15...

  8. Development of structural design criteria for ITER.

    SciTech Connect (OSTI)

    Majumdar, S.

    1998-06-22T23:59:59.000Z

    The irradiation environment experienced by the in-vessel components of fusion reactors such as HER presents structural design challenges not envisioned in the development of existing structural design criteria such as the ASME Code or RCC-MR. From the standpoint of design criteria, the most significant issues stem from the irradiation-induced changes in material properties, specifically the reduction of ductility, strain hardening capability, and fracture toughness with neutron irradiation. Recently, Draft 7 of the interim ITER structural design criteria (ISDC), which provide new rules for guarding against such problems, was released for trial use by the ITER designers. The new rules, which were derived from a simple model based on the concept of elastic follow up factor, provide primary and secondary stress limits as functions of uniform elongation and ductility. The implication of these rules on the allowable surface heat flux on typical first walls made of type 316 stainless steel and vanadium alloys are discussed.

  9. Genome-Wide Identification and 3D Modeling of Proteins involved in DNA Damage Recognition and Repair (Final Report)

    SciTech Connect (OSTI)

    Ruben A. Abagyan, PhD

    2004-04-15T23:59:59.000Z

    OAK-B135 DNA Damage Recognition and Repair (DDR and R) proteins play a critical role in cellular responses to low-dose radiation and are associated with cancer. the authors have performed a systematic, genome-wide computational analysis of genomic data for human genes involved in the DDR and R process. The significant achievements of this project include: (1) Construction of the computational pipeline for searching DDR and R genes, building and validation of 3D models of proteins involved in DDR and R; (2) Functional and structural annotation of the 3D models and generation of comprehensive lists of suggested knock-out mutations; (3) Important improvement of macromolecular docking technology and its application to predict the DNA-Protein complex conformation; (4) Development of a new algorithm for improved analysis of high-density oligonucleotide arrays for gene expression profiling; (5) Construction and maintenance of the DNA Damage Recognition and Repair Database; and (6) Producing 14 research papers (10 published and 4 in preparation).

  10. Predictive capabilities, analysis and experiments for Fusion Nuclear Technology, and ITER R D

    SciTech Connect (OSTI)

    Not Available

    1991-01-01T23:59:59.000Z

    This report discusses the following topics on ITER research and development: trituim modeling; liquid metal blanket modeling; free surface liquid metal studies; and thermal conductance and thermal control experiments and modeling. (LIP)

  11. Parent Involvement

    E-Print Network [OSTI]

    Howard, Jeff W.

    2005-05-10T23:59:59.000Z

    To be successful, a 4-H program must have parent involvement. Although 4-H leaders and Extension agents may interest young people in becoming members, they need the parents' goodwill and support to keep them interested, enthusiastic and active. Here...

  12. Assessment of CONTAIN and MELCOR for performing LOCA and LOVA analyses in ITER

    SciTech Connect (OSTI)

    Merrill, B.J.; Hagrman, D.L.; Gaeta, M.J.; Petti, D.A.

    1994-09-01T23:59:59.000Z

    This report describes the results of an assessment of the CONTAIN and MELCOR computer codes for ITER LOCA and LOVA applications. As part of the assessment, the results of running a test problem that describes an ITER LOCA are presented. It is concluded that the MELCOR code should be the preferred code for ITER severe accident thermal hydraulic analyses. This code will require the least modification to be appropriate for calculating thermal hydraulic behavior in ITER relevant conditions that include vacuum, cryogenics, ITER temperatures, and the presence of a liquid metal test module. The assessment of the aerosol transport models in these codes concludes that several modifications would have to be made to CONTAIN and/or MELCOR to make them applicable to the aerosol transport part of severe accident analysis in ITER.

  13. ITER | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) EnvironmentalGyroSolé(tm)Hydrogen StorageITERITER Subscribe to RSS - ITER ITER is a

  14. US ITER Project Brad Nelson

    E-Print Network [OSTI]

    power supply in San Giorgio di Piano, Italy #12;FY 2014 Partner Achievements 9/23/14 FESAC ITER Progress Central Solenoid Steady State Electrical Network Tokamak Cooling Water System Toroidal Field Conductor #12 · Roughing pumps · Pellet injection · Tokamak cooling water system · Vacuum auxiliary system · Ion

  15. The roadmap to magnetic confinement fusion Cutaway of the ITER tokamak. ( ITER)

    E-Print Network [OSTI]

    Hampshire, Damian

    The roadmap to magnetic confinement fusion Cutaway of the ITER tokamak. (© ITER) There are two ways breeding concepts [8] . Roadmap beyond ITER The ITER project has mapped out a road map to a commercial is the most promising for power generation (Table 2) [9] . #12;Table 2. "Fast track" fusion roadmap Facility

  16. ITERATED INTEGRALS OF SUPERCONNECTIONS KIYOSHI IGUSA

    E-Print Network [OSTI]

    Igusa, Kiyoshi

    ITERATED INTEGRALS OF SUPERCONNECTIONS KIYOSHI IGUSA Abstract. Iterated integration of a connection gives the holonomy or parallel transport of the connection. Iterated integration of a superconnection gives something else which we call a "superconnection parallel transport." We ask under what conditions

  17. AND THEIR PREDICTIONS FOR ITER D. R. MIKKELSEN

    E-Print Network [OSTI]

    Hammett, Greg

    15) Chalmers University of Technology, Göteborg, Sweden Abstract A number of proposed tokamak thermal transport models for several reasons. Firstly, to enhance our confidence in extrapolations of energy range of existing tokamak data. This has led to the development of the ITER Profile Database [2] which

  18. Edge-Localized Iterative Reconstruction for Computed Tomography

    E-Print Network [OSTI]

    1 Edge-Localized Iterative Reconstruction for Computed Tomography Zhou Yu Student Member, IEEE) can greatly improve the quality of computed tomography (CT) images. In particular, MBR can recover at significantly reduced computational cost. Index Terms--Computed tomography, model based reconstruc- tion

  19. Edge-Localized Iterative Reconstruction for Computed Tomography

    E-Print Network [OSTI]

    Edge-Localized Iterative Reconstruction for Computed Tomography Zhou Yu Student Member, IEEE, Jean the quality of computed tomography (CT) images. In particular, MBR can recover fine details and small features reduced computational cost. Index Terms--Computed tomography, model based reconstruc- tion, coordinate

  20. ITERATIVE TOTAL VARIATION REGULARIZATION WITH NON-QUADRATIC FIDELITY

    E-Print Network [OSTI]

    Burger, Martin

    , AND STANLEY J. OSHER Abstract. A generalized iterative regularization procedure based on the total variation still eliminate high-frequency noise. However, the ROF model (1.1) has certain limitations. Meyer has with the norm ||w|| = inf g,w= ·g ess sup x |g(x)| , Meyer provided arguments in favour of considering elements

  1. Iterative solutions of simultaneous equations 

    E-Print Network [OSTI]

    Laycock, Guyron Brantley

    1962-01-01T23:59:59.000Z

    ITERATIVE SOLUTIONS OP SIKJLTANEOUS EQUATIONS G~cn Hrantlep I aycock Approved. as to style snd, content by& (Chairman of Committee) E. c. (Head. of Department August 1/62 ACKNOWLEDGEMENT The author wishes to thank Dr. Hi A. Luther for his time sn4.... . . . ~ ~ . . ~ III. JACOBI AND 6AUSS-SEIDEL METHODS I V ~ C ONCLUS I GN ~ ~ ~ a ~ ~ ~ t ~ ~ ~ ~ a ~ 1 ~ ~ ~ ~ ~ ~ 9 ~ . ~ 18 V BIBLIOGRAPHY ~ ~ ~ o ~ ~ t ~ ~ ~ ~ 1 ~ ~ ~ VI ~ APPENDIX ~ ~ o ~ ~ e ~ o ~ ~ o o ~ ~ ~ . 22 Px'ogl am Lisliiixlgs...

  2. Simulations of plasma behavior during pellet injection in ITER

    SciTech Connect (OSTI)

    Klaywittaphat, P., E-mail: thawatchai@siit.tu.ac.th; Onjun, T. [Thammasat University, School of Manufacturing Systems and Mechanical Engineering, Sirindhorn International Institute of Technology (Thailand)

    2012-06-15T23:59:59.000Z

    Plasma behavior during pellet injection in ITER is investigated using a 1.5D BALDUR integrated predictive modeling code. In these simulations, the pellet ablation is described using the neutral gas shielding (NGS) model developed by Parks and Turnbull [Phys. Fluids 21, 1735 (1978)]. The NGS pellet ablation model that includes the {nabla}B drift effect is coupled with a plasma core transport model, which is a combination of an MMM95 anomalous transport model and an NCLASS neoclassical transport model. The combination of core transport models, together with pellet model, is used to simulate the time evolution of plasma current, ion and electron temperatures, and density profiles for ITER standard type-I ELMy H-mode discharges during the pellet injection. It is found that the injection of pellet can result in either enhancement or degradation of plasma performance. The {nabla}B drift effect on the pellet deposition is very strong in ITER. The plasma density with high field side pellets, which favorable with the {nabla}B drift effect, is much higher and pellet can penetrate much deeper than that with low field side pellets.

  3. submitted to International Journal of Computer Vision June, 2002 The Dual-Bootstrap Iterative Closest Point Algorithm with

    E-Print Network [OSTI]

    Bystroff, Chris

    submitted to International Journal of Computer Vision June, 2002 The Dual-Bootstrap Iterative initial estimate. By contrast, the Dual-Bootstrap ICP algorithm only requires an initial estimate iteratively "bootstraps" both the region over which the model is accurate and the chosen transformation model

  4. submitted to International Journal of Computer Vision June, 2002 The Dual-Bootstrap Iterative Closest Point Algorithm with

    E-Print Network [OSTI]

    Bystroff, Chris

    submitted to International Journal of Computer Vision June, 2002 The Dual-Bootstrap Iterative initial estimate. By contrast, the Dual-Bootstrap ICP algorithm only requires an initial estimate iteratively \\bootstraps" both the region over which the model is accurate and the chosen transformation model

  5. Research at ITER towards DEMO: Specific reactor diagnostic studies to be carried out on ITER

    SciTech Connect (OSTI)

    Krasilnikov, A. V.; Kaschuck, Y. A.; Vershkov, V. A.; Petrov, A. A.; Petrov, V. G.; Tugarinov, S. N. [Institution Project center ITER, Moscow (Russian Federation)

    2014-08-21T23:59:59.000Z

    In ITER diagnostics will operate in the very hard radiation environment of fusion reactor. Extensive technology studies are carried out during development of the ITER diagnostics and procedures of their calibration and remote handling. Results of these studies and practical application of the developed diagnostics on ITER will provide the direct input to DEMO diagnostic development. The list of DEMO measurement requirements and diagnostics will be determined during ITER experiments on the bases of ITER plasma physics results and success of particular diagnostic application in reactor-like ITER plasma. Majority of ITER diagnostic already passed the conceptual design phase and represent the state of the art in fusion plasma diagnostic development. The number of related to DEMO results of ITER diagnostic studies such as design and prototype manufacture of: neutron and ?–ray diagnostics, neutral particle analyzers, optical spectroscopy including first mirror protection and cleaning technics, reflectometry, refractometry, tritium retention measurements etc. are discussed.

  6. ITER | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) EnvironmentalGyroSolé(tm)Hydrogen StorageITER

  7. US ITER Moving Forward Video

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin TransitionProgram | Departmentcontributes 75% of2014 EIA120ITER

  8. Overview of ITER ProjectOverview of ITER Project --organizational structure,organizational structure,

    E-Print Network [OSTI]

    /Research Plans 3. Basic Research in support of ITER · Experimental and Theoretical Plasma Research · R

  9. Pellet fueling technology development leading to efficient fueling of ITER burning plasmas

    SciTech Connect (OSTI)

    Baylor, L.R.; Combs, S.K.; Jernigan, T.C.; Houlberg, W.A.; Owen, L.W.; Rasmussen, D.A.; Maruyama, S.; Parks, P.B. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6169 (United States)

    2005-05-15T23:59:59.000Z

    Pellet injection is the primary fueling technique planned for core fueling of ITER [ITER Technical Basis 2002 ITER EDA Documentation Series (Vienna: IAEA)] burning plasmas. Efficient core plasma fueling with deuterium and tritium D-T is a requirement for achieving high fusion gain and it cannot be achieved with gas fueling. Injection of pellets from the inner wall has been shown on present day tokamaks to provide efficient fueling and is planned for use on ITER. Modeling of the fueling deposition from inner wall pellet injection using the Parks ExB drift model indicates that pellets have the capability to fuel well inside the separatrix. Gas fueling calculations show very poor neutral penetration due to the high density and wide scrape off layer. Isotopically mixed D-T pellets can provide efficient tritium fueling that will minimize tritium wall loading when compared to gas puffing. Currently the performance of the ITER inner wall guide tube design is under test with initial results indicating that pellet speeds in excess of 300 m/s will lead to fragmented pellets. The ITER pellet injection technology requirements and remaining development issues are discussed along with a plan to reach the design goal for employment on ITER.

  10. ITER Project Status Fusion Energy Sciences

    E-Print Network [OSTI]

    to capped value) ORNL 100% Tokamak Cooling Water System PPPL 75% Steady State Electrical Network PPPL 14 Project Office April 9, 2014 #12;Major Progress: Construction Site 04/09/14 FESAC/Sauthoff 2 Photo: ITER Organization · September 2013 #12;Major Progress: ITER Headquarters Building 04/09/14 FESAC/Sauthoff 3 #12

  11. Insights from US ITER: Strategies for Accelerating

    E-Print Network [OSTI]

    Insights from US ITER: Strategies for Accelerating Fusion Energy as a Project Ned Sauthoff US ITER Project Manager SOFE Town Hall Meeting | June 27, 2011 #12;1. Treat fusion energy as a project, rather than a program. Mission: ·Rapid materials and fusion systems development, leading

  12. ITERATED INTEGRALS OF SUPERCONNECTIONS KIYOSHI IGUSA

    E-Print Network [OSTI]

    Igusa, Kiyoshi

    ITERATED INTEGRALS OF SUPERCONNECTIONS KIYOSHI IGUSA Abstract. Starting with a Z-graded superconnection on a graded vector bun- dle over a smooth manifold M, we show how Chen's iterated integration of such a superconnection over smooth simplices in M gives an A functor if and only if the superconnection is flat

  13. ITER site contest counts down Junichi Miura

    E-Print Network [OSTI]

    Thermonuclear Experimental Reactor (ITER), an international project to use nuclear fusion energy for electric on a site for the project. The ITER project envisions using thermonuclear fusion to generate huge amounts heavy hydrogen and tritium used for fuel in the fusion reaction are heated in a vacuum receptacle at 100

  14. Iterative Speech Enhancement With Spectral Constraints

    E-Print Network [OSTI]

    Texas at Dallas, University of

    Iterative Speech Enhancement With Spectral Constraints John H. Hansen and Mark A. Clements Georgia iterative speech enhancementtechnique based on spectral constraints is presented in this paper estimate of a speech waveform in additive white noise. Thenew approach applies inter- and intra

  15. ITER --"INTERNATIONAL THERMONUCLEAR EXPERIMENTAL RESEARCH PROGRAM".

    E-Print Network [OSTI]

    ITER -- "INTERNATIONAL THERMONUCLEAR EXPERIMENTAL RESEARCH PROGRAM". ORGANIZATION TO DIRECT WORLD plasmas and thermonuclear burn processes (cost -$1.5-36)2. (2) An expanded, more ambitious international Thermonuclear Experimental Research Program" by L. J. Perkins #12;NORMAL-CONDUCTING COPPER OPTIONS FOR THE ITER

  16. Annex I ITER Organization Service Contract General Conditions...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Annex I ITER Organization Service Contract General Conditions (2014) Page 1 of 21 GENERAL CONDITIONS FOR ITER ORGANIZATION SERVICE CONTRACTS (2014) Definitions...

  17. IAEA-CN-SO/F-I-4 ITER: CONCEPT DEFINITION*

    E-Print Network [OSTI]

    way. 1. INTRODUCTION The activity of the International Thermonuclear Experimental Reactor (ITER. * The activity of the International Thermonuclear Experimental Reactor (ITER) is conducted under the auspices

  18. ITER Ion Cyclotron Heating and Fueling Systems

    SciTech Connect (OSTI)

    Rasmussen, D.A. [Oak Ridge National Laboratory (United States); Baylor, L.R. [Oak Ridge National Laboratory (United States); Combs, S.K. [Oak Ridge National Laboratory (United States); Fredd, E. [Princeton Plasma Physics Laboratory (United States); Goulding, R.H. [Oak Ridge National Laboratory (United States); Hosea, J. [Princeton Plasma Physics Laboratory (United States); Swain, D.W. [Oak Ridge National Laboratory (United States)

    2005-04-15T23:59:59.000Z

    The ITER burning plasma and advanced operating regimes require robust and reliable heating and current drive and fueling systems. The ITER design documents describe the requirements and reference designs for the ion cyclotron and pellet fueling systems. Development and testing programs are required to optimize, validate and qualify these systems for installation on ITER.The ITER ion cyclotron system offers significant technology challenges. The antenna must operate in a nuclear environment and withstand heat loads and disruption forces beyond present-day designs. It must operate for long pulse lengths and be highly reliable, delivering power to a plasma load with properties that will change throughout the discharge. The ITER ion cyclotron system consists of one eight-strap antenna, eight rf sources (20 MW, 35-65 MHz), associated high-voltage DC power supplies, transmission lines and matching and decoupling components.The ITER fueling system consists of a gas injection system and multiple pellet injectors for edge fueling and deep core fueling. Pellet injection will be the primary ITER fuel delivery system. The fueling requirements will require significant extensions in pellet injector pulse length ({approx}3000 s), throughput (400 torr-L/s,) and reliability. The proposed design is based on a centrifuge accelerator fed by a continuous screw extruder. Inner wall pellet injection with the use of curved guide tubes will be utilized for deep fueling.

  19. Dynamic simulation of a proposed ITER tritium processing system

    SciTech Connect (OSTI)

    Kuan, W.; Abdou, M.A. [Univ. of California, Los Angeles, CA (United States); Scott W.R. [Los Alamos National Lab., NM (United States)

    1995-10-01T23:59:59.000Z

    Dynamically simulating the fuel cycle in a fusion reactor is crucial to developing a better understanding of the safe and reliable operation of this complex system. In this work, we propose a tritium processing system for ITER`s plasma exhaust. The dynamic simulation of this proposed system is then performed with the TRUFFLES (TRitiUm Fusion Fuel cycLE dynamic Simulation) model. The fuel management, storage, and fueling operations are developed and coupled with previous cryopump and fuel cleanup unit subsystems to fully realize the complete torus exhaust flow cycle. Results show that tritium inventories will vary widely depending upon reactor operation, individual subsystem and unit operation designs. A diverse collection of batch-controlled subsystems with changes in their processing parameters are simulated in this work. In particular, the effects from the fuel management subsystem`s fuel reserve and tank switching times are quantified using sensitivity studies. 6 refs., 10 figs., 2 tabs.

  20. Pellet Fueling and Control of Burning Plasmas in ITER

    SciTech Connect (OSTI)

    Baylor, Larry R [ORNL; Parks, P. B. [General Atomics; Jernigan, Thomas C [ORNL; Caughman, John B [ORNL; Combs, Stephen Kirk [ORNL; Foust, Charles R [ORNL; Houlberg, Wayne A [ORNL; Maruyama, S. [ITER International Team, Garching, Germany; Rasmussen, David A [ORNL

    2007-01-01T23:59:59.000Z

    Pellet injection from the inner wall is planned for use on ITER as the primary core fueling system since gas fueling is expected to be highly inefficient in burning plasmas. Tests of the inner wall guide tube have shown that 5mm pellets with up to 300 m/s speeds can survive intact and provide the necessary core fueling rate. Modeling and extrapolation of the inner wall pellet injection experiments from today's smaller tokamaks leads to the prediction that this method will provide efficient core fueling beyond the pedestal region. Using pellets for triggering of frequent small edge localized modes is an attractive additional benefit that the pellet injection system can provide. A description of the ITER pellet injection system capabilities for fueling and ELM triggering are presented and performance expectations and fusion power control aspects are discussed.

  1. Iterative Information Model Development Protein sequence

    E-Print Network [OSTI]

    Protein Information Resource (PIR) Protein Science Team (11) Executive Team Members Dr. Winona Barker. Cecilia Arighi, Senior Protein Scientist, Research Assistant Professor Natalia Petrova, PhD StudentPIR Director Dr. Cathy Wu Professor PIR Director Dr. Cathy Wu Professor Bioinformatics Team (9) Executive Team

  2. Overview of ITER Project Activities in the U.S.

    E-Print Network [OSTI]

    procurement packages for bid. ­ Need to contribute team members to international ITER Organization to the ITER Organization for common expenses ­ Staff for the ITER Organization at expected US rates #12, standard components #12;Evolution of the ITER cost from $500M to $1.122B: Sum of all components ($M

  3. Value iteration for (switched) homogeneous systems

    E-Print Network [OSTI]

    Dahleh, Munther A.

    In this note, we prove that dynamic programming value iteration converges uniformly for discrete-time homogeneous systems and continuous-time switched homogeneous systems. For discrete-time homogeneous systems, rather than ...

  4. Michel Claessens michel.claessens@iter.org

    E-Print Network [OSTI]

    on the manufacturing of critical components, were among the important issues discussed at the eighth meeting. Photos of the Council Meeting can be found at: http://www.iter.org/gallery/pr_2011_06_ic8 Additional

  5. ITERATIVE METHODS FOR NEUTRON TRANSPORT EIGENVALUE PROBLEMS

    E-Print Network [OSTI]

    Graham, Ivan

    Abstract. We discuss iterative methods for computing criticality in nuclear reactors. In general as the inner solver. Key words. neutron transport, criticality, generalised eigenvalue problem, symmetry. Reactor criticality problems. Climate change is a challenging problem of great contemporary interest

  6. EQUILIBRIUM RECONSTRUCTION ITERATION FLOW-CHART

    E-Print Network [OSTI]

    EQUILIBRIUM RECONSTRUCTION ITERATION FLOW-CHART SUME AND 0 n GET 1 AND C0 j GET J1 AND 1 n GET 2 the total stored (kinetic + magnetic) energy density #12;TYPICAL FIELD CONFIGURATIONS acuum Field Low Beta

  7. A domain decomposition method of stochastic PDEs: An iterative solution techniques using a two-level scalable preconditioner

    SciTech Connect (OSTI)

    Subber, Waad, E-mail: wsubber@connect.carleton.ca; Sarkar, Abhijit, E-mail: abhijit_sarkar@carleton.ca

    2014-01-15T23:59:59.000Z

    Recent advances in high performance computing systems and sensing technologies motivate computational simulations with extremely high resolution models with capabilities to quantify uncertainties for credible numerical predictions. A two-level domain decomposition method is reported in this investigation to devise a linear solver for the large-scale system in the Galerkin spectral stochastic finite element method (SSFEM). In particular, a two-level scalable preconditioner is introduced in order to iteratively solve the large-scale linear system in the intrusive SSFEM using an iterative substructuring based domain decomposition solver. The implementation of the algorithm involves solving a local problem on each subdomain that constructs the local part of the preconditioner and a coarse problem that propagates information globally among the subdomains. The numerical and parallel scalabilities of the two-level preconditioner are contrasted with the previously developed one-level preconditioner for two-dimensional flow through porous media and elasticity problems with spatially varying non-Gaussian material properties. A distributed implementation of the parallel algorithm is carried out using MPI and PETSc parallel libraries. The scalabilities of the algorithm are investigated in a Linux cluster.

  8. CHARACTERISTICS OF THE H-MODE PEDESTAL AND EXTRAPOLATION TO ITER

    SciTech Connect (OSTI)

    OSBORNE,TH; CORDEY,JG; GROEBNER,RJ; HATAE,T; HUBBARD,A; HORTON,LD; KAMADA,Y; KRITZ,A; LAO,LL; LEONARD,AW; LOARTE,A; MAHDAVI,MA; MOSSESSIAN,D; ONJUN,T; OSSENPENKO,M; ROGNLIEN,TD; SAIBNE,G; SNYDER,PB; SUGIHARA,M; SHURYGIN,R; THOMSEN,K; WADE,MR; WILSON,HR; XU,XQ; YATSU,K

    2002-11-01T23:59:59.000Z

    A271 CHARACTERISTICS OF THE H-MODE PEDESTAL AND EXTRAPOLATION TO ITER. The peeling-ballooning mode model for edge stability along with a model for the H-mode transport barrier width is used as an approach to estimating the H-mode pedestal conditions in ITER. Scalings of the barrier width based on ion-orbit loss, neutral penetration, and turbulence suppression are examined and empirical scalings of the barrier width are presented. An empirical scaling for the pedestal {beta} is derived based on ideas from stability and the empirical width scaling. The impact of the stability model and other factors on ELM size is discussed.

  9. Y.ShimomuraY.Shimomura ITER Joint Central TeamITER Joint Central Team

    E-Print Network [OSTI]

    Structure #12;ICRF All metal Vacuum Transmission Line Support · Avoid dielectric material · Cool through SLIP JOINT COOLING IN COOLING OUT mm VTL GETTER PUMP #12;Mode Converter Support Structure Standard Novgorod and CRPP Lausanne ECRH/ECCD for ITER: ITER-task: Remote steering antenna for ECRH/ECCD #12

  10. JJ, IAP Cambridge January 20101 Fusion Energy & ITER:Fusion Energy & ITER

    E-Print Network [OSTI]

    JJ, IAP Cambridge January 20101 Fusion Energy & ITER:Fusion Energy & ITER: Challenges Billions ITERITER startsstarts DEMODEMO decisiondecision:: Fusion impact? Energy without greenEnergy Fusion fuel: deuterium et tritium Deuterium: plenty in the ocean Tritium: made in situ from Lithium

  11. ITER risk workshop facilitator guide

    SciTech Connect (OSTI)

    Medina, Patricia [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    The goal of planning risk management is to make everyone involved in a program aware that risk should be a consideration in the design, development, and fielding of a system. Risk planning is a tool to assess and mitigate events that might adversely impact the program. Therefore, risk management increases the probability/likelihood of program success and can help to avoid program crisis management and improve problem solving by managing risk early in the acquisition cycle.

  12. ITER risk workshop participant guide

    SciTech Connect (OSTI)

    Medina, Patricia [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    The goal of planning risk management is to make everyone involved in a program aware that risk should be a consideration in the design, development, and fielding of a system. Risk planning is a tool to assess and mitigate events that might adversely impact the program. Therefore, risk management increases the probability/likelihood of program success and can help to avoid program crisis management and improve problem solving by managing risk early in the acquisition cycle.

  13. Pellet Fueling Technology Development Leading to Efficient Fueling of ITER Burning Plasmas

    SciTech Connect (OSTI)

    Baylor, Larry R [ORNL; Combs, Stephen Kirk [ORNL; Jernigan, Thomas C [ORNL; Houlberg, Wayne A [ORNL; Maruyama, S. [ITER International Team, Garching, Germany; Owen, Larry W [ORNL; Parks, P. B. [General Atomics; Rasmussen, David A [ORNL

    2005-01-01T23:59:59.000Z

    Pellet injection is the primary fueling technique planned for central fueling of the ITER burning plasma, which is a requirement for achieving high fusion gain. Injection of pellets from the inner wall has been shown on present day tokamaks to provide efficient fueling and is planned for use on ITER [1,2]. Significant development of pellet fueling technology has occurred as a result of the ITER R&D process. Extrusion rates with batch extruders have reached more than 1/2 of the ITER design specification of 1.3 cm3/s [3] and the ability to fuel efficiently from the inner wall by injecting through curved guide tubes has been demonstrated on several fusion devices. Modeling of the fueling deposition from inner wall pellet injection has been done using the Parks et al. ExB drift model [4] shows that inside launched pellets of 3mm size and speeds of 300 m/s have the capability to fuel well inside the separatrix. Gas fueling on the other hand is calculated to have very poor fueling efficiency due to the high density and wide scrape off layer compared to current machines. Isotopically mixed D/T pellets can provide efficient tritium fueling that will minimize tritium wall loading when compared to gas puffing of tritium. In addition, the use of pellets as an ELM trigger has been demonstrated and continues to be investigated as an ELM mitigation technique. During the ITER CDA and EDA the U.S. was responsible for ITER fueling system design and R&D and is in good position to resume this role for the ITER pellet fueling system. Currently the performance of the ITER guide tube design is under investigation. A mockup is being built that will allow tests with different pellet sizes and repetition rates. The results of these tests and their implication for fueling efficiency and central fueling will be discussed. The ITER pellet injection technology developments to date, specified requirements, and remaining development issues will be presented along with a plan to reach the design goal in time for employment on ITER.

  14. US solid breeder blanket design for ITER

    SciTech Connect (OSTI)

    Gohar, Y.; Attaya, H.; Billone, M.; Lin, C.; Johnson, C.; Majumdar, S.; Smith, D. (Argonne National Lab., IL (USA)); Goranson, P.; Nelson, B.; Williamson, D.; Baker, C. (Oak Ridge National Lab., TN (USA)); Raffray, A.; Badawi, A.; Gorbis, Z.; Ying, A.; Abdou, M. (California Univ., Los Angeles, CA (USA)); Sviatoslavsky, I.; Blanchard, J.; Mogahed, E.; Sawan, M.; Kulcinski, G. (Wisconsin Univ., Madison, WI (USA))

    1990-09-01T23:59:59.000Z

    The US blanket design activity has focused on the developments and the analyses of a solid breeder blanket concept for ITER. The main function of this blanket is to produce the necessary tritium required for the ITER operation and the test program. Safety, power reactor relevance, low tritium inventory, and design flexibility are the main reasons for the blanket selection. The blanket is designed to operate satisfactorily in the physics and the technology phases of ITER without the need for hardware changes. Mechanical simplicity, predictability, performance, minimum cost, and minimum R D requirements are the other criteria used to guide the design process. The design aspects of the blanket are summarized in this paper. 2 refs., 7 figs., 3 tabs.

  15. Plan and Strategy for ITER Blanket Testing in Japan

    SciTech Connect (OSTI)

    Enoeda, Mikio [Japan Atomic Energy Research Institute (Japan); Akiba, Masato [Japan Atomic Energy Research Institute (Japan); Tanaka, Satoru [University of Tokyo (Japan); Shimizu, Akihiko [Kyushu University (Japan); Hasegawa, Akira [Tohoku University (Japan); Konishi, Satoshi [Kyoto University (Japan); Kimura, Akihiko [Kyoto University (Japan); Kohyama, Akira [Kyoto University (Japan); Sagara, Akio [National Institute of Fusion Science (Japan); Muroga, Takeo [National Institute of Fusion Science (Japan)

    2005-05-15T23:59:59.000Z

    The Fusion Council of Japan has established the long-term program for the development of blanket in 1999. In the program, the solid breeder blanket was selected as the primary candidate blanket of the fusion power demonstration plant in Japan, while liquid breeder blankets and high temperature solid breeder blanket have been identified as the attractive advanced blanket. Japan Atomic Energy Research Institute (JAERI) is leading the development of solid breeder blankets, while, universities and National Institute for Fusion Science (NIFS) are developing the advanced blankets for potential options of the fusion power demonstration plant and commercial power plants. ITER blanket module testing is regarded as one of the most important milestones, by which integrity of candidate blanket design is qualified for the fusion power demonstration plant, together with material irradiation data by International Fusion Material Irradiation Facility (IFMIF). Japan is investigating the possibility of testing all types of blankets under TBWG framework with both of JAERI and universities/NIFS involvements. This paper presents a plan and strategy for the development of test blanket modules and ITER blanket module testing in Japan.

  16. Volumetric quantification of lung nodules in CT with iterative reconstruction (ASiR and MBIR)

    SciTech Connect (OSTI)

    Chen, Baiyu [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 and Carl E. Ravin Advanced Imaging Laboratories, Duke University, Durham, North Carolina 27705 (United States)] [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 and Carl E. Ravin Advanced Imaging Laboratories, Duke University, Durham, North Carolina 27705 (United States); Barnhart, Huiman [Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina 27705 (United States)] [Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina 27705 (United States); Richard, Samuel [Carl E. Ravin Advanced Imaging Laboratories, Duke University, Durham, North Carolina 27705 and Department of Radiology, Duke University, Durham, North Carolina 27705 (United States)] [Carl E. Ravin Advanced Imaging Laboratories, Duke University, Durham, North Carolina 27705 and Department of Radiology, Duke University, Durham, North Carolina 27705 (United States); Robins, Marthony [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 (United States)] [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 (United States); Colsher, James [Department of Radiology, Duke University, Durham, North Carolina 27705 (United States)] [Department of Radiology, Duke University, Durham, North Carolina 27705 (United States); Samei, Ehsan [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 (United States) [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 (United States); Carl E. Ravin Advanced Imaging Laboratories, Duke University, Durham, North Carolina 27705 (United States); Department of Radiology, Duke University, Durham, North Carolina 27705 (United States); Department of Physics, Department of Biomedical Engineering, and Department of Electronic and Computer Engineering, Duke University, Durham, North Carolina 27705 (United States)

    2013-11-15T23:59:59.000Z

    Purpose: Volume quantifications of lung nodules with multidetector computed tomography (CT) images provide useful information for monitoring nodule developments. The accuracy and precision of the volume quantification, however, can be impacted by imaging and reconstruction parameters. This study aimed to investigate the impact of iterative reconstruction algorithms on the accuracy and precision of volume quantification with dose and slice thickness as additional variables.Methods: Repeated CT images were acquired from an anthropomorphic chest phantom with synthetic nodules (9.5 and 4.8 mm) at six dose levels, and reconstructed with three reconstruction algorithms [filtered backprojection (FBP), adaptive statistical iterative reconstruction (ASiR), and model based iterative reconstruction (MBIR)] into three slice thicknesses. The nodule volumes were measured with two clinical software (A: Lung VCAR, B: iNtuition), and analyzed for accuracy and precision.Results: Precision was found to be generally comparable between FBP and iterative reconstruction with no statistically significant difference noted for different dose levels, slice thickness, and segmentation software. Accuracy was found to be more variable. For large nodules, the accuracy was significantly different between ASiR and FBP for all slice thicknesses with both software, and significantly different between MBIR and FBP for 0.625 mm slice thickness with Software A and for all slice thicknesses with Software B. For small nodules, the accuracy was more similar between FBP and iterative reconstruction, with the exception of ASIR vs FBP at 1.25 mm with Software A and MBIR vs FBP at 0.625 mm with Software A.Conclusions: The systematic difference between the accuracy of FBP and iterative reconstructions highlights the importance of extending current segmentation software to accommodate the image characteristics of iterative reconstructions. In addition, a calibration process may help reduce the dependency of accuracy on reconstruction algorithms, such that volumes quantified from scans of different reconstruction algorithms can be compared. The little difference found between the precision of FBP and iterative reconstructions could be a result of both iterative reconstruction's diminished noise reduction at the edge of the nodules as well as the loss of resolution at high noise levels with iterative reconstruction. The findings do not rule out potential advantage of IR that might be evident in a study that uses a larger number of nodules or repeated scans.

  17. Parallel computation of multigroup reactivity coefficient using iterative method

    SciTech Connect (OSTI)

    Susmikanti, Mike [Center for Development of Nuclear Informatics, National Nuclear Energy Agency of Indonesia PUSPIPTEK Area, Tangerang (Indonesia)] [Center for Development of Nuclear Informatics, National Nuclear Energy Agency of Indonesia PUSPIPTEK Area, Tangerang (Indonesia); Dewayatna, Winter [Center for Nuclear Fuel Technology, National Nuclear Energy Agency of Indonesia PUSPIPTEK Area, Tangerang (Indonesia)] [Center for Nuclear Fuel Technology, National Nuclear Energy Agency of Indonesia PUSPIPTEK Area, Tangerang (Indonesia)

    2013-09-09T23:59:59.000Z

    One of the research activities to support the commercial radioisotope production program is a safety research target irradiation FPM (Fission Product Molybdenum). FPM targets form a tube made of stainless steel in which the nuclear degrees of superimposed high-enriched uranium. FPM irradiation tube is intended to obtain fission. The fission material widely used in the form of kits in the world of nuclear medicine. Irradiation FPM tube reactor core would interfere with performance. One of the disorders comes from changes in flux or reactivity. It is necessary to study a method for calculating safety terrace ongoing configuration changes during the life of the reactor, making the code faster became an absolute necessity. Neutron safety margin for the research reactor can be reused without modification to the calculation of the reactivity of the reactor, so that is an advantage of using perturbation method. The criticality and flux in multigroup diffusion model was calculate at various irradiation positions in some uranium content. This model has a complex computation. Several parallel algorithms with iterative method have been developed for the sparse and big matrix solution. The Black-Red Gauss Seidel Iteration and the power iteration parallel method can be used to solve multigroup diffusion equation system and calculated the criticality and reactivity coeficient. This research was developed code for reactivity calculation which used one of safety analysis with parallel processing. It can be done more quickly and efficiently by utilizing the parallel processing in the multicore computer. This code was applied for the safety limits calculation of irradiated targets FPM with increment Uranium.

  18. Symbolic Opportunistic Policy Iteration for Factored-Action MDPs

    E-Print Network [OSTI]

    Iteration (OPI), which is a novel convergent algorithm lying between VI and MPI, that applies policy to converge. This new algorithm, Opportunistic Policy Iteration (OPI), constrains a select subset

  19. Chirac calls ITER essential for planet's future

    E-Print Network [OSTI]

    fusion reactor. "Today, our energy consumption has put us in danger. It's mainly based on oil, gasChirac calls ITER essential for planet's future CADARACHE, France, June 30 (AFP) - French President in southern France as vital to the planet's future, praising European solidarity in sealing the deal. "This

  20. Using Iterative Compilation to Reduce Energy Consumption

    E-Print Network [OSTI]

    Gheorghita, Valentin

    or to re- duce power. Most transformations require loop re- structuring. Although a large number.v.gheorghita,h.corporaal,a.a.basten}@tue.nl Keywords: Iterative Compilation, Program Optimization, Energy Consumption, Program Transformation. Abstract. This is emphasized by new demands added to compilers, like reducing static code size, energy consumption or power

  1. AN ALGEBRAIC DESCRIPTION OF ITERATIVE DECODING SCHEMES

    E-Print Network [OSTI]

    Soljanin, Emina

    AN ALGEBRAIC DESCRIPTION OF ITERATIVE DECODING SCHEMES ELKE OFFER AND EMINA SOLJANIN Abstract University of Technology, D- 80290 Munich, Germany, elke@lnt.e-technik.tu-muenchen.de Mathematical Sciences Research Center, Bell Labs, Lucent Technologies, Murray Hill, NJ 07974, USA. emina@lucent.com 1 #12;2 E

  2. Neil Calder neil.calder@iter.org

    E-Print Network [OSTI]

    on the ITER site, financed by the European Union. Approval was also given to for a Test Blanket Module Program to demonstrate the scientific and technological feasibility of fusion power for energy purposes. Fusion plant that is safe and reliable, environmentally responsible and economically viable, with abundant

  3. CONTRACTIVITY IN TURBO ITERATIONS Phillip A. Regalia

    E-Print Network [OSTI]

    Regalia, Phillip A.

    CONTRACTIVITY IN TURBO ITERATIONS Phillip A. Regalia Department of Communications, Image Fourier 91011 Evry cedex France Phillip.Regalia@int-evry.fr ABSTRACT The turbo decoding algorithm has met with intense study over the past decade, in an attempt to harness the full power of the "turbo principle". Here

  4. US ITER Project Status Fusion Power Associates

    E-Print Network [OSTI]

    .5 Gigajoule stored energy capacity) Central Solenoid ­ The Heartbeat of ITER 12/10/13 FPA/Sauthoff 1,000 tonne assembled and is being prepared for testing Photo: Seco Warwick (wiebodzin. Poland) 11 #12;Toroidal Field Conductor Specs: 18 toroidal field coils are designed to have ·Total magnetic energy of 41 gigajoules

  5. Michel Claessens michel.claessens@iter.org

    E-Print Network [OSTI]

    . This two-day meeting brought together senior representatives from all seven ITER Members--China-of-a-kind global collaboration. Europe will contribute almost half of the costs of its construction, while the other six Members to this joint international venture (China, India, Japan, the Republic of Korea

  6. Joint News Release ELEVENTH ITER NEGOTIATIONS MEETING

    E-Print Network [OSTI]

    of Science and Technology of China Department of International Co-operation Luo Delong luodl@mail.most.govJoint News Release ELEVENTH ITER NEGOTIATIONS MEETING CHENGDU , CHINA, 24OCTOBER 2005 Delegations from China, European Union, Japan, the Republic of Korea, the Russian Federation and the United States

  7. Dale M. Meade MFE Plenary Session on ITER Costs

    E-Print Network [OSTI]

    Dale M. Meade MFE Plenary Session on ITER Costs 2002 Fusion Summer Study Snowmass, CO July 9, 2002 FIRE Lighting the Way to Fusion http://fire.pppl.gov A Comparison of Unit Costs for FIRE and ITER #12;A Comparison of Unit Costs for FIRE and ITER · A simple rule of thumb for comparing costs of similar devices

  8. ITER HEAT REMOVAL SYSTEM SYSTEM & PROCESS CONTROL DESIGN

    E-Print Network [OSTI]

    Raffray, A. René

    normal pulse operation, the heat deposited in the in-vessel components is released into the environment. Ito 1 , P. Lorenzetto 4 , Y. Okawa 5 1 ITER Joint Central Team, 11025 North Torrey Pines Road, La Jolla, CA, 92037, USA; 2 ITER Joint Central Team, Naka, Japan; 3 ITER Joint Central Team, Garching

  9. A Conditional Logic for Iterated Belief Revision Laura Giordano

    E-Print Network [OSTI]

    Giordano, Laura

    A Conditional Logic for Iterated Belief Revision Laura Giordano DSTA ­ Universitâ?? a del Piemonte Abstract. In this paper we propose a conditional logic IBC to rep­ resent iterated belief revision. We define an iterated belief revision system by strengthening the postulates proposed by Darwiche and Pearl

  10. Budget Planning Meeting FY 2007 Status of ITER Negotiations

    E-Print Network [OSTI]

    Budget Planning Meeting ­ FY 2007 Status of ITER Negotiations Michael Roberts, Director ITER Preparations of $5M · Using FY05 $5M to continue to get ready for MIE project · Maintaining U.S. visiting experts · Further establishing U.S. ITER Project Office · Fulfilling DOE project management requirements

  11. Iterative Water-filling for Gaussian Vector Multiple Access Channels

    E-Print Network [OSTI]

    Li, Tiffany Jing

    Iterative Water-filling for Gaussian Vector Multiple Access Channels W. Yu, W. Rhee, S. Boyd, and J. Cioffi Zhenlei Shen Lehigh University March 29, 2005 Zhenlei Shen (Lehigh) Iterative Water-filling for Gaussian Vector Multiple Access ChannelsMarch 29, 2005 1 / 13 #12;1 Quick Review 2 Iterative Water

  12. Non-iterative Voltage Stability

    SciTech Connect (OSTI)

    Makarov, Yuri V.; Vyakaranam, Bharat; Hou, Zhangshuan; Wu, Di; Meng, Da; Wang, Shaobu; Elbert, Stephen T.; Miller, Laurie E.; Huang, Zhenyu

    2014-09-30T23:59:59.000Z

    This report demonstrates promising capabilities and performance characteristics of the proposed method using several power systems models. The new method will help to develop a new generation of highly efficient tools suitable for real-time parallel implementation. The ultimate benefit obtained will be early detection of system instability and prevention of system blackouts in real time.

  13. Simulations of Alpha Wall Load in ITER. Final report

    SciTech Connect (OSTI)

    Carlsson, Johan

    2010-10-20T23:59:59.000Z

    The partially DOE funded International Thermonuclear Experimental Reactor (ITER) will produce massive amounts of energetic charged alpha particles, which are imperfectly confined by a strong magnetic field. The wall of the experiment is designed to withstand an estimated wall load from these fusion alpha particles, but the accuracy of this estimate needs to be improved to avoid potentially catastrophic surprises when the experiment becomes operational. We have added a more accurate, gyro-dynamic model of particle motion to the existing drift-dynamic model in the DELTA5D simulation software used for the project. We have also added the ability to load a detailed engineering model of the wall and use it in the simulations.

  14. on the Establishment of the ITER International Fusion Energy Organization for the Joint Implementation of the ITER Project

    E-Print Network [OSTI]

    AGREEMENT on the Establishment of the ITER International Fusion Energy Organization for the Joint Fusion Energy Organization Article 2 Purpose of the ITER Organization Article 3 Functions of the ITER://fusionforenergy.europa.eu/downloads/aboutf4e/l_35820061216en00620081.pdf #12;Preamble The European Atomic Energy Community (hereinafter

  15. Progress in the Integrated Simulation of Thermal-Hydraulic Operation of the ITER Magnet System

    E-Print Network [OSTI]

    Bagnasco, M; Bessette, D; Marinucci, C

    2010-01-01T23:59:59.000Z

    A new integrated computer code is being developed for the simulations of the overall behavior of the ITER magnet cryo-system. The existing THEA, FLOWER and POWER codes, assembled as modules of a computational environment (Super-Magnet) have been upgraded to perform global simulations of the cooling circuit for the ITER magnet system. The thermal coupling resulting from the generic geometric configurations has been implemented to realize quasi-three-dimensional simulations of the winding pack. In this paper we present details on the model.

  16. Optical dumps for H-alpha and visible spectroscopy in ITER

    SciTech Connect (OSTI)

    Andreenko, E. N.; Alekseev, A. G.; Gorshkov, A. V.; Orlovskiy, I. I. [NRC Kurchatov Institute, 123182 Moscow (Russian Federation)

    2014-08-21T23:59:59.000Z

    High-reflective Beryllium cover of ITER first wall (R?30–60%) causes remarkable increase of divertor stray light component (DSL). Optical dumps are well-known solution for DSL attenuation. In this work few types of optical dumps have been examined both by modeling and experimental studies. Taking into account the limitations, induced by ITER first wall design, OD optimized design has been proposed which could decrease divertor stray light component by 10..100 times depending on incidence angle of light.

  17. Damage to nearby divertor components of ITER-like devices during giant ELMs and disruptions

    E-Print Network [OSTI]

    Harilal, S. S.

    Damage to nearby divertor components of ITER-like devices during giant ELMs and disruptions. Fusion 50 (2010) 115004 (7pp) doi:10.1088/0029-5515/50/11/115004 Damage to nearby divertor components. The simulation results of the integrated modelling indicate a significant potential damage of the divertor nearby

  18. HEART SEGMENTATION WITH AN ITERATIVE CHAN-VESE OLIVIER ROUSSEAU, YVES BOURGAULT

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    HEART SEGMENTATION WITH AN ITERATIVE CHAN-VESE ALGORITHM OLIVIER ROUSSEAU, YVES BOURGAULT Abstract. This paper presents 2D and 3D applications of the Chan-Vese model to heart and trachea segmentation. We is to segment the heart muscle from high resolution CT scans of the thorax and to produce meshes

  19. Approaches to confined alpha diagnostics on ITER

    SciTech Connect (OSTI)

    Fisher, R.K. [General Atomics, PO Box 85608, San Diego, California 92186-5608 (United States)

    2004-10-01T23:59:59.000Z

    Three approaches to obtain information on the confined fast alphas in the International Thermonuclear Experimental Reactor (ITER) are proposed. The first technique measures the energetic charge exchange (CX) neutrals that result from the alpha collision-induced knock-on fuel ion tails undergoing electron capture on the MeV D neutral beams planned for heating and current drive. The second technique measures the energetic knock-on neutron tail due to alphas using the lengths of the proton recoil tracks produced by neutron collisions in nuclear emulsions. The range of the 14 to 20 MeV recoil protons increases by {approx}140 {mu}m per MeV. The third approach would measure the CX helium neutrals resulting from confined alphas capturing two electrons in the ablation cloud surrounding a dense gas jet that has been proposed for disruption mitigation in ITER.

  20. Thermomechanical analysis of the ITER breeding blanket

    SciTech Connect (OSTI)

    Majumdar, S.; Gruhn, H. [Argonne National Lab., IL (United States); Gohar, Y.; Giegerich, M. [Max-Planck-Institut fuer Plasmaphysik, Muenchen (Germany). ITER Joint Central Team

    1997-03-01T23:59:59.000Z

    Thermomechanical performance of the ITER breeding blanket is an important design issue because it requires first, that the thermal expansion mismatch between the blanket structure and the blankets internals (such as, beryllium multiplier and tritium breeders) can be accommodated without creating high stresses, and second, that the thermomechanical deformation of various interfaces within the blanket does not create high resistance to heat flow and consequent unacceptably high temperatures in the blanket materials. Thermomechanical analysis of a single beryllium block sandwiched between two stainless steel plates was carried out using the finite element code ABAQUS to illustrate the importance of elastic deformation on the temperature distributions. Such an analysis for the whole ITER blanket needs to be conducted in the future. Uncertainties in the thermomechanical contact analysis can be reduced by bonding the beryllium blocks to the stainless steel plates by a thin soft interfacial layer.

  1. Main challenges for ITER optical diagnostics

    SciTech Connect (OSTI)

    Vukolov, K. Yu.; Orlovskiy, I. I.; Alekseev, A. G.; Borisov, A. A.; Andreenko, E. N.; Kukushkin, A. B.; Lisitsa, V. S.; Neverov, V. S. [Tokamak Physics Institute, NRC Kurchatov Institute, 123182 Moscow (Russian Federation)

    2014-08-21T23:59:59.000Z

    The review is made of the problems of ITER optical diagnostics. Most of these problems will be related to the intensive neutron radiation from hot plasma. At a high level of radiation loads the most types of materials gradually change their properties. This effect is most critical for optical diagnostics because of degradation of optical glasses and mirrors. The degradation of mirrors, that collect the light from plasma, basically will be induced by impurity deposition and (or) sputtering by charge exchange atoms. Main attention is paid to the search of glasses for vacuum windows and achromatic lens which are stable under ITER irradiation conditions. The last results of irradiation tests in nuclear reactor of candidate silica glasses KU-1, KS-4V and TF 200 are presented. An additional problem is discussed that deals with the stray light produced by multiple reflections from the first wall of the intense light emitted in the divertor plasma.

  2. Disruptions, loads, and dynamic response of ITER

    SciTech Connect (OSTI)

    Nelson, B.; Riemer, B.; Sayer, R.; Strickler, D. [Oak Ridge National Lab., TN (United States); Barabaschi, P.; Ioki, K.; Johnson, G.; Shimizu, K.; Williamson, D. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany). International Thermonuclear Experimental Reactor (ITER) Team

    1995-12-31T23:59:59.000Z

    Plasma disruptions and the resulting electromagnetic loads are critical to the design of the vacuum vessel and in-vessel components of the International Thermonuclear Experimental Reactor (ITER). This paper describes the status of plasma disruption simulations and related analysis, including the dynamic response of the vacuum vessel and in-vessel components, stresses and deflections in the vacuum vessel, and reaction loads in the support structures.

  3. AIR: fused Analytical and Iterative Reconstruction method for computed tomography

    E-Print Network [OSTI]

    Yang, Liu; Qi, Sharon X; Gao, Hao

    2013-01-01T23:59:59.000Z

    Purpose: CT image reconstruction techniques have two major categories: analytical reconstruction (AR) method and iterative reconstruction (IR) method. AR reconstructs images through analytical formulas, such as filtered backprojection (FBP) in 2D and Feldkamp-Davis-Kress (FDK) method in 3D, which can be either mathematically exact or approximate. On the other hand, IR is often based on the discrete forward model of X-ray transform and formulated as a minimization problem with some appropriate image regularization method, so that the reconstructed image corresponds to the minimizer of the optimization problem. This work is to investigate the fused analytical and iterative reconstruction (AIR) method. Methods: Based on IR with L1-type image regularization, AIR is formulated with a AR-specific preconditioner in the data fidelity term, which results in the minimal change of the solution algorithm that replaces the adjoint X-ray transform by the filtered X-ray transform. As a proof-of-concept 2D example of AIR, FB...

  4. Occupational Radiation Exposure Analysis of US ITER DCLL TBM

    SciTech Connect (OSTI)

    Merrill, Brad J; Cadwallader, Lee C; Dagher, Mohamad

    2007-08-01T23:59:59.000Z

    This report documents an Occupational Radiation Exposure (ORE) analysis that was performed for the US International Thermonuclear Experimental Reactor (ITER) Dual Coolant Lead Lithium (DCLL) Test Blanket Module (TBM). This analysis was performed with the QADMOD dose code for anticipated maintenance activities for this TBM concept and its ancillary systems. The QADMOD code was used to model the PbLi cooling loop of this TBM concept by specifying gamma ray source terms that simulated radioactive material within the piping, valves, heat exchanger, permeator, pump, drain tank, and cold trap of this cooling system. Estimates of the maintenance tasks that will have to be performed and the time required to perform these tasks where developed based on either expert opinion or on industrial maintenance experience for similar technologies. This report details the modeling activity and the calculated doses for the maintenance activities envisioned for the US DCLL TBM.

  5. Iterative methods for solving the pressure problem at multiphase filtration

    E-Print Network [OSTI]

    Vabishchevich, P

    2011-01-01T23:59:59.000Z

    Applied problems of oil and gas recovery are studied numerically using the mathematical models of multiphase fluid flows in porous media. The basic model includes the continuity equations and the Darcy laws for each phase, as well as the algebraic expression for the sum of saturations. Primary computational algorithms are implemented for such problems using the pressure equation. In this paper, we highlight the basic properties of the pressure problem and discuss the necessity of their fulfillment at the discrete level. The resulting elliptic problem for the pressure equation is characterized by a non-selfadjoint operator. Possibilities of approximate solving the elliptic problem are considered using the iterative methods. Special attention is given to the numerical algorithms for calculating the pressure on parallel computers.

  6. An iterative technique for solving equations of statistical equilibrium

    E-Print Network [OSTI]

    L. B. Lucy

    2001-03-21T23:59:59.000Z

    Superlevel partitioning is combined with a simple relaxation procedure to construct an iterative technique for solving equations of statistical equilibrium. In treating an $N$-level model atom, the technique avoids the $N^{3}$ scaling in computer time for direct solutions with standard linear equation routines and also does not fail at large $N$ due to the accumulation of round-off errors. In consequence, the technique allows detailed model atoms with $N \\ga 10^{3}$, such as those required for iron peak elements, to be incorporated into diagnostic codes for analysing astronomical spectra. Tests are reported for a 394-level Fe II ion and a 1266-level Ni I--IV atom.

  7. US Demo test blankets in ITER

    SciTech Connect (OSTI)

    Waganer, L.M.; Lee, V.D [McDonnell Douglas Aerospace, St. Louis, MO (United States); Abdou, M.A.; Ying, A.Y. [Univ. of California, Los Angeles, CA (United States); Hua, T.; Sze, D.K. [Argonne National Lab., IL (United States); Dagher, M.A. [Rockwell International Corp., Canoga Park, CA (United States)

    1996-12-31T23:59:59.000Z

    This paper summarizes the current status of the Demo blanket test systems and how the ITER reactor design and operations are being accommodated. The US blanket program is planning to develop a liquid metal breeder and a solid breeder blanket for testing and evaluation. The test blanket modules will have prototypical components, materials, and coolants representative of power reactor systems. The modules are to be located in the ITER horizontal test ports and installed/removed with special remote handling equipment. Adjacent ITER blanket neutronic and temperature conditions suggest the use of an isolation frame surrounding the test blanket modules or submodules. This frame will also provide additional shielding to protect the adjacent vacuum vessel. The frame and blanket module are attached to the surrounding backplate to transfer static and dynamic loads. All coolants and tritium-bearing fluids will be routed out of the midplane port to special heat exchangers and tritium separation systems. Special remote handling equipment is being designed to install and extract the test blanket modules. Dedicated transporters will be used to move the blanket and shielding modules to dedicated hot cells. Special facility areas will be provided immediately outside the port areas for the heat exchangers, pumps, and tritium-separation systems. 1 ref., 6 figs.

  8. The Evolution Of Phrase Structure In Bayesian Iterated Artificial Language Learning: A Linguistic System’s Evolution After The Emergence Of An Unbounded Combinatorial Capacity 

    E-Print Network [OSTI]

    Saldana, Carmen

    2013-08-15T23:59:59.000Z

    of the actual system or the cognitive underpinnings that allow it? Using Bayesian Iterated Artificial Language Models, the present work will show the evolution of Phrase Structure through cultural transmission in populations of Bayesian learners from a trade...

  9. Benchmarking ICRF Full-wave Solvers for ITER

    SciTech Connect (OSTI)

    R. V. Budny, L. Berry, R. Bilato, P. Bonoli, M. Brambilla, R. J. Dumont, A. Fukuyama, R. Harvey, E. F. Jaeger, K. Indireshkumar, E. Lerche, D. McCune, C. K. Phillips, V. Vdovin, J. Wright, and members of the ITPA-IOS

    2011-01-06T23:59:59.000Z

    Abstract Benchmarking of full-wave solvers for ICRF simulations is performed using plasma profiles and equilibria obtained from integrated self-consistent modeling predictions of four ITER plasmas. One is for a high performance baseline (5.3 T, 15 MA) DT H-mode. The others are for half-field, half-current plasmas of interest for the pre-activation phase with bulk plasma ion species being either hydrogen or He4. The predicted profiles are used by six full-wave solver groups to simulate the ICRF electromagnetic fields and heating, and by three of these groups to simulate the current-drive. Approximate agreement is achieved for the predicted heating power for the DT and He4 cases. Factor of two disagreements are found for the cases with second harmonic He3 heating in bulk H cases. Approximate agreement is achieved simulating the ICRF current drive.

  10. p-points in iterated forcing extensions

    E-Print Network [OSTI]

    Roitman, Judith A.

    1978-05-03T23:59:59.000Z

    Ma. By Fact 4, U aiterated ccc extensions whose length has uncountable cofinality. These theorems are proved in §3. In §4 we indicate how...

  11. Looking northeast over the ITER construction site

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes |Is Your HomeLatestCenterLogging inLooking northeast over the ITER

  12. US ITER toroidal field coil conductor produc

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening aTurbulence may bedieselsummer gasoline price0 UPCNational ITER

  13. Y.ShimomuraY.Shimomura ITER Joint Central TeamITER Joint Central Team

    E-Print Network [OSTI]

    mobility between ITER and domestic programmes #12;Reactor Development: Stable fusion power production;0 0.2 0.4 0.6 0.8 1 0 0.5 1 1.5 2 2.5 3 3.5 Vp, km/s 11 12 13 14 23 21 22 X HFS pellet speed ~ 300 m

  14. Edge plasma studies for ITER and related B2 code development

    SciTech Connect (OSTI)

    Weitzner, H.; Braams, B.

    1992-03-01T23:59:59.000Z

    During the past three years the B2 code has been entirely re-written. This contract report will serve as a provisional user guide for the new (B2.5) code, which is hereby made available to the ITER modellers. A definitive description of the new code will be prepared in the course of the present year. The following changes to the physics (with respect to the B2 code version now in wide use) should be noted. The representation of the atomic physics now relies on rate coefficients obtained from either of two code packages: the ADPAK collection developed by R. A. Hulse of Princeton PPL and the STRAHL collection developed by K. Behringer of Garching and JET. These are used to prepare tables of rate coefficients for ionization, recombination, radiation, and charge exchange, involving hydrogen and any impurities that are of interest. A fluid model is now available to describe the neutral species. The neutral fluid is governed by a convection-diffusion equation of similar form as all the other equations solved in the code; the diffusivity is based on the thermal velocity and the mean free path for ionization and charge exchange. The code has been extensively modified in the interest of clarity of design and ease of use. The internal documentation has been expanded, so that almost all variables are now clearly described and every small segment of code has a clearly stated purpose. Some steps were made toward including a full treatment of the electric potential and of diamagnetic transport. The poloidal transport is no longer tied to the parallel transport by a simple factor B[sub [theta

  15. Edge plasma studies for ITER and related B2 code development

    SciTech Connect (OSTI)

    Weitzner, H.; Braams, B.

    1992-03-01T23:59:59.000Z

    During the past three years the B2 code has been entirely re-written. This contract report will serve as a provisional user guide for the new (B2.5) code, which is hereby made available to the ITER modellers. A definitive description of the new code will be prepared in the course of the present year. The following changes to the physics (with respect to the B2 code version now in wide use) should be noted. The representation of the atomic physics now relies on rate coefficients obtained from either of two code packages: the ADPAK collection developed by R. A. Hulse of Princeton PPL and the STRAHL collection developed by K. Behringer of Garching and JET. These are used to prepare tables of rate coefficients for ionization, recombination, radiation, and charge exchange, involving hydrogen and any impurities that are of interest. A fluid model is now available to describe the neutral species. The neutral fluid is governed by a convection-diffusion equation of similar form as all the other equations solved in the code; the diffusivity is based on the thermal velocity and the mean free path for ionization and charge exchange. The code has been extensively modified in the interest of clarity of design and ease of use. The internal documentation has been expanded, so that almost all variables are now clearly described and every small segment of code has a clearly stated purpose. Some steps were made toward including a full treatment of the electric potential and of diamagnetic transport. The poloidal transport is no longer tied to the parallel transport by a simple factor B{sub {theta}}/B, but includes diffusive contributions. A two-dimensional elliptic equation is solved to obtain the electric potential, assuming an anomalous cross-field resistivity and thermo-electric coefficient of the plasma.

  16. TRANSP Tests Of TGLF and Predictions For ITER

    SciTech Connect (OSTI)

    none,; Budny, Robert; Yuan, Xingqiu

    2014-02-26T23:59:59.000Z

    Gyro kinetic simulations of turbulence capture some of the features observed in transport, fluctuations, and correlations measured in tokamak plasmas. These codes calculations are CPU intensive, and are not practical for incorporation in present time-dependant transport codes, so reduced models based on these gyro kinetic codes are being used. An example is the TGLF model [1] which is a quasilinear gyrofluid model calibrated to nonlinear results from the GYRO code [2]. Recently TGLF has been incorporated into TRANSP. Analysis of experimental data using TRANSP with such models provides fundamental understanding of turbulent transport. Predictions of ITER performance with various plasma scenarios using such models are useful for optimizing design and for exposing issues that can be addressed in present experiments and theory. For instance, which combinations of heating, torquing, and current drive are optimal. Another application is for nuclear licensing (e.g. system integrity, neutron rates). Others are generating inputs for design of diagnostic systems and for theoretical studies. An example of the later is Alfv´en Eigenmode and AE-induced loss of fast ions. The beam ion distribution can either enhance or reduce the alpha pressure drive of the AE instability. The AE instability can cause dangerous amounts of fast ion losses, as was seen in TFTR.

  17. Design, manufacture and initial operation of the beryllium components of the JET ITER-like wall

    E-Print Network [OSTI]

    Riccardo, V; Matthews, G F; Nunes, I; Thompson, V; Villedieu, E; Contributors, JET EFDA

    2013-01-01T23:59:59.000Z

    The aim of the JET ITER-like Wall Project was to provide JET with the plasma facing material combination now selected for the DT phase of ITER (bulk beryllium main chamber limiters and a full tungsten divertor) and, in conjunction with the upgraded neutral beam heating system, to achieve ITER relevant conditions. The design of the bulk Be plasma facing components had to be compatible with increased heating power and pulse length, as well as to reuse the existing tile supports originally designed to cope with disruption loads from carbon based tiles and be installed by remote handling. Risk reduction measures (prototypes, jigs, etc) were implemented to maximize efficiency during the shutdown. However, a large number of clashes with existing components not fully captured by the configuration model occurred. Restarting the plasma on the ITER-like Wall proved much easier than for the carbon wall and no deconditioning by disruptions was observed. Disruptions have been more threatening than expected due to the redu...

  18. Diverse Power Iteration Embeddings and Its Applications

    SciTech Connect (OSTI)

    Huang H.; Yoo S.; Yu, D.; Qin, H.

    2014-12-14T23:59:59.000Z

    Abstract—Spectral Embedding is one of the most effective dimension reduction algorithms in data mining. However, its computation complexity has to be mitigated in order to apply it for real-world large scale data analysis. Many researches have been focusing on developing approximate spectral embeddings which are more efficient, but meanwhile far less effective. This paper proposes Diverse Power Iteration Embeddings (DPIE), which not only retains the similar efficiency of power iteration methods but also produces a series of diverse and more effective embedding vectors. We test this novel method by applying it to various data mining applications (e.g. clustering, anomaly detection and feature selection) and evaluating their performance improvements. The experimental results show our proposed DPIE is more effective than popular spectral approximation methods, and obtains the similar quality of classic spectral embedding derived from eigen-decompositions. Moreover it is extremely fast on big data applications. For example in terms of clustering result, DPIE achieves as good as 95% of classic spectral clustering on the complex datasets but 4000+ times faster in limited memory environment.

  19. A review of ITER blanket designs

    SciTech Connect (OSTI)

    Green, L.; Carelli, M.D.; Stefani, F. [Westinghouse Science & Technology Center, Pittsburgh, PA (United States); Morgan, G.D. [McDonnell Douglas Corp., St. Louis, MO (United States); Mattas, R. [Argonne National Lab., IL (United States)

    1994-11-01T23:59:59.000Z

    Changes in ITER requirements and conditions in the Engineering Design Activity (EDA), and the desire to obtain greater operating flexibility, led to a reconsideration of the ITER Conceptual Design Activity (CDA) blanket designs. The current strategy is to follow a two-tiered development approach: The reference design blanket is non-breeding, and satisfies only the basic performance phase (BPP) functional requirements. This blanket would need to be changed out for the extended performance (EPP). A lower level development effort is also underway on a tritium-breeding blanket. The decision as to which of the two designs to adopt will be made at the end of a two-year development effort. This paper describes the present candidate blankets and the issues associated with each of them. The reference design is a non-breeding, low temperature, low pressure, water cooled, austenitic stainless steel (316SS) blanket/shield (BS). The first wall (FW), which may be integral with or separate from the BS, is a bonded copper-alloy/SS structure with a beryllium coating. Critical issues here are copper-SS bonding, fabricability, and radiation damage and stress corrosion cracking of the SS. The breeding blanket utilizes vanadium alloy structural material, with lithium as the breeder. The coolants are either lithium (self-cooled) or high pressure helium. The primary issues here are the need to electrically insulate the flow channels, the qualification of vanadium as a structural material, and the fabrication of large vanadium structures.

  20. San Diego 01.05.2001 Power and Particle Exhaust in ITER Slide 1 by G. Janeschitz, et.al. _______________________________________________________________________ ITER

    E-Print Network [OSTI]

    San Diego 01.05.2001 Power and Particle Exhaust in ITER Slide 1 by G. Janeschitz, et.al. ITER. Pacher, G. Pacher, R. Tivey, M. Sugihara, JCT and HTs #12;San Diego; 01.05.2001 Power and Particle to pump #12;San Diego; 01.05.2001 Power and Particle Exhaust in ITER Slide 3 by G. Janeschitz. ITER

  1. Properties of Iterated Multiple Belief Revision Dongmo Zhang

    E-Print Network [OSTI]

    Zhang, Dongmo

    in the community of belief revision[2][5][9][10][13][17]. The major concern in the research is the reducibilityProperties of Iterated Multiple Belief Revision Dongmo Zhang School of Computing and Information investigate the properties of iterated multiple belief revision. We examine several typical assumptions

  2. Iterated Belief Revision and Conditional Logic Laura Giordano

    E-Print Network [OSTI]

    Torino, Università di

    /01/2001; 17:22; p.1 #12; 2 well known Triviality Result [5], that claims that no signi#12;cant belief revisionIterated Belief Revision and Conditional Logic Laura Giordano DSTA - Universit#18;a del Piemonte a conditional logic called IBC to represent iterated belief revision systems. We propose a set of postulates

  3. BLIND ITERATIVE RESTORATION OF IMAGES WITH SPATIALLY-VARYING BLUR

    E-Print Network [OSTI]

    Bardsley, John

    BLIND ITERATIVE RESTORATION OF IMAGES WITH SPATIALLY-VARYING BLUR John Bardsley Stuart Jefferies (PSF) by using a combination of methods including sectioning and phase diversity blind deconvolution whose PSFs are correlated and approximately spatially-invariant, and apply iterative blind deconvolution

  4. ITERATED INTEGRALS OF SUPERCONNECTIONS 0902a KIYOSHI IGUSA

    E-Print Network [OSTI]

    Igusa, Kiyoshi

    ITERATED INTEGRALS OF SUPERCONNECTIONS 0902a KIYOSHI IGUSA Abstract. Iterated integration of a superconnection gives something else which we call a "superconnection parallel transport." We ask under what the superconnection parallel transports give homotopies and higher homotopies of these chain maps. This happens

  5. Japan, EU reach basic agreement over ITER The Yomiuri Shimbun

    E-Print Network [OSTI]

    Japan, EU reach basic agreement over ITER The Yomiuri Shimbun The government and the European Union to the unsuccessful candidate country. Japan and France, the EU's candidate, have been bidding to host the facility bidder's country. The ITER project participants--Japan, China, the EU, Russia, South Korea and the United

  6. Proving termination by policy iteration Damien Masse1

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    NSAD 2012 Proving termination by policy iteration Damien Mass´e1 Lab-Sticc, UMR 6285 UBO conditions for program termination. Restricting ourselves to affine programs and the abstract domain. Keywords: Abstract interpretation, policy iteration, template constraint matrices, termination analysis. 1

  7. Fractional Variational Iteration Method for Fractional Nonlinear Differential Equations

    E-Print Network [OSTI]

    Guo-cheng Wu

    2010-07-12T23:59:59.000Z

    Recently, fractional differential equations have been investigated via the famous variational iteration method. However, all the previous works avoid the term of fractional derivative and handle them as a restricted variation. In order to overcome such shortcomings, a fractional variational iteration method is proposed. The Lagrange multipliers can be identified explicitly based on fractional variational theory.

  8. October 6, 1997 ITER L-Mode Con nement Database

    E-Print Network [OSTI]

    October 6, 1997 ITER L-Mode Con nement Database S.M. Kaye and the ITER Con nement Database Working Group Abstract This paper describes the content of an L-mode database that has been compiled with data, and Tore-Supra. The database consists of a total of 2938 entries, 1881 of which are in the L-phase while

  9. A Turbo Iteration Algorithm In 16QAM Hierarchical Modulation

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    A Turbo Iteration Algorithm In 16QAM Hierarchical Modulation Xu Zhe Electric and Information on the turbo code, OFDM modulation and 16QAM hierarchical modulation to increase the flexibility, and in the high SNR, it can also gain a high BER performance of low priority bit stream. Keywords- turbo iteration

  10. Final Report on ITER Task Agreement 81-10

    SciTech Connect (OSTI)

    Brad J. Merrill

    2009-01-01T23:59:59.000Z

    An International Thermonuclear Experimental Reactor (ITER) Implementing Task Agreement (ITA) on Magnet Safety was established between the ITER International Organization (IO) and the Idaho National Laboratory (INL) Fusion Safety Program (FSP) during calendar year 2004. The objectives of this ITA were to add new capabilities to the MAGARC code and to use this updated version of MAGARC to analyze unmitigated superconductor quench events for both poloidal field (PF) and toroidal field (TF) coils of the ITER design. This report documents the completion of the work scope for this ITA. Based on the results obtained for this ITA, an unmitigated quench event in an ITER larger PF coil does not appear to be as severe an accident as in an ITER TF coil.

  11. Radioactivity measurements of ITER materials using TFTR D-T neutron field

    SciTech Connect (OSTI)

    Kumar, A.; Abdou, M.A. [Univ. of California, Los Angeles, CA (United States); Kugel, H.W. [Princeton Univ., NJ (United States)] [and others

    1994-12-31T23:59:59.000Z

    TFTR successfully initiated trace tritium plasma experiments in mid-November 1993. During the coming year, the TFTR plasma tritium fraction is scheduled to be increased to at least 50%. The availability of larger amounts of D-T fusion neutrons in the high power D-T plasma phase of TFTR provides an useful opportunity to directly measure D-T neutron induced radioactivity in a realistic tokamak-environment in materials of vital interest to ITER. These measurements are invaluable for characterizing short and long lived radioactivity in various ITER candidate materials, for validating complex neutron transport calculations, and for meeting fusion reactor licensing requirements. The radioactivity measurements at TFTR will involve potential ITER materials that include stainless steel 316, vanadium-alloy, copper, iron, nickel, chromium, vanadium, titanium, manganese, cobalt, molybdenum, zinc, niobium, zirconium, tungsten, lead, tin, silicon, etc. Small samples of these materials will be irradiated in varying neutron energy spectra at the vacuum vessel first wall. These irradiated samples will then be counted for {gamma}-radioactivity at different cooling times to get extensive information on as many {gamma}-emitting radioactive products as feasible.

  12. ITER Central Solenoid Coil Insulation Qualification

    SciTech Connect (OSTI)

    Martovetsky, Nicolai N [ORNL] [ORNL; Mann Jr, Thomas Latta [ORNL] [ORNL; Miller, John L [ORNL] [ORNL; Freudenberg, Kevin D [ORNL] [ORNL; Reed, Richard P [Cryogenic Materials, Inc.] [Cryogenic Materials, Inc.; Walsh, Robert P [Florida State University] [Florida State University; McColskey, J D [National Institute of Standards and Technology (NIST), Boulder] [National Institute of Standards and Technology (NIST), Boulder; Evans, D [Advanced Cryogenic Materials] [Advanced Cryogenic Materials

    2010-01-01T23:59:59.000Z

    An insulation system for ITER Central Solenoid must have sufficiently high electrical and structural strength. Design efforts to bring stresses in the turn and layer insulation within allowables failed. It turned out to be impossible to eliminate high local tensile stresses in the winding pack. When high local stresses can not be designed out, the qualification procedure requires verification of the acceptable structural and electrical strength by testing. We built two 4x4 arrays of the conductor jacket with two options of the CS insulation and subjected the arrays to 1.2 million compressive cycles at 60 MPa and at 76 K. Such conditions simulated stresses in the CS insulation. We performed voltage withstand tests and after end of cycling we measured the breakdown voltages between in the arrays. After that we dissectioned the arrays and studied micro cracks in the insulation. We report details of the specimens preparation, test procedures and test results.

  13. ITER L-Mode Confinement Database

    SciTech Connect (OSTI)

    S.M. Kaye and the ITER Confinement Database Working Group

    1997-10-01T23:59:59.000Z

    This paper describes the content of an L-mode database that has been compiled with data from Alcator C-Mod, ASDEX, DIII, DIII-D, FTU, JET, JFT-2M, JT-60, PBX-M, PDX, T-10, TEXTOR, TFTR, and Tore-Supra. The database consists of a total of 2938 entries, 1881 of which are in the L-phase while 922 are ohmically heated (OH) only. Each entry contains up to 95 descriptive parameters, including global and kinetic information, machine conditioning, and configuration. The paper presents a description of the database and the variables contained therein, and it also presents global and thermal scalings along with predictions for ITER. The L-mode thermal confinement time scaling was determined from a subset of 1312 entries for which the thermal confinement time scaling was provided.

  14. ITER CENTRAL SOLENOID COIL INSULATION QUALIFICATION

    SciTech Connect (OSTI)

    Martovetsky, N N; Mann, T L; Miller, J R; Freudenberg, K D; Reed, R P; Walsh, R P; McColskey, J D; Evans, D

    2009-06-11T23:59:59.000Z

    An insulation system for ITER Central Solenoid must have sufficiently high electrical and structural strength. Design efforts to bring stresses in the turn and layer insulation within allowables failed. It turned out to be impossible to eliminate high local tensile stresses in the winding pack. When high local stresses can not be designed out, the qualification procedure requires verification of the acceptable structural and electrical strength by testing. We built two 4 x 4 arrays of the conductor jacket with two options of the CS insulation and subjected the arrays to 1.2 million compressive cycles at 60 MPa and at 76 K. Such conditions simulated stresses in the CS insulation. We performed voltage withstand tests and after end of cycling we measured the breakdown voltages between in the arrays. After that we dissectioned the arrays and studied micro cracks in the insulation. We report details of the specimens preparation, test procedures and test results.

  15. The development of iterative and cascade methods for the rapid synthesis of ladder polyether natural products

    E-Print Network [OSTI]

    Heffron, Timothy Paul

    2005-01-01T23:59:59.000Z

    I. The Development of Methods for the Iterative Synthesis of Polytetrahydropyrans An iterative method comprising chain homologation, epoxidation, 6-endo cyclization, and protiodesilylation was developed. Notable achievements ...

  16. Atomic data for the ITER Core Imaging X-ray Spectrometer

    SciTech Connect (OSTI)

    Clementson, J; Beiersdorfer, P; Biedermann, C; Bitter, M; Delgado-Aparicio, L F; Graf, A; Gu, M F; Hill, K W; Barnsley, R

    2012-06-15T23:59:59.000Z

    The parameters of the ITER core plasmas will be measured using the Core Imaging X-ray Spectrometer (CIXS), a high-resolution crystal spectrometer focusing on the L-shell spectra of highly ionized tungsten atoms. In order to correctly infer the plasma properties accurate atomic data are required. Here, some aspects of the underlying physics are discussed using experimental data and theoretical predictions from modeling.

  17. Information Technology Systems for Fusion Industry and ITER Project

    SciTech Connect (OSTI)

    Putvinskaya, N.; Bulasheva, N.; Cole, G.; Dillon, T.; Frieman, E.; Sabado, M.; Schissel, D. (and others)

    2005-04-15T23:59:59.000Z

    The industrial developments in the fusion industry will have to overcome numerous technical challenges and will have a strong need for modern information technology (IT) systems.The fusion industry has manifested itself with an unprecedented international collaboration, the International Thermonuclear Experimental Reactor (ITER). Data accumulated in ITER will be the major output of the project and will create the knowledge base for a future fusion power plant. A modern and effective information infrastructure will be critical to the success of the ITER project.To accumulate and maintain the knowledge base at all stages of the project, we propose to build an integrated information system for ITER: ITER Information Plant (IIP). IIP will minimize lost experiment time and accelerate the understanding, interpretation, and planning of fusion experiments. IIP will allow to reap maximum benefits from the project's scientific and technological achievements, make the ITER results accessible to hundreds of researchers worldwide. This will facilitate collaboration, dramatically increasing the pace of scientific and technological discovery and the rate at which practical use is made of these discoveries.As the first of its kind, the ITER Information Plant could be used in the future as a prototype IT system for national and international fusion projects, in which multicountry collaboration, distributed work sites and operations are catalysts for success.

  18. Data gathering to build and validate small-scale social models for simulation. Two ways: strict control and stake-holders involvement

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    Data gathering to build and validate small-scale social models for simulation. Two ways: strict.rouchier@univmed.fr Kyoto, 2005 - 10 - 13 Modelling and the search for realism Social simulation using multi-agent paradigm (sometimes called "agent-based simulation" or "simulation with agents") has developed quickly in the last

  19. Examination of the Entry to Burn and Burn Control for the ITER 15 MA Baseline and Other Scenarios

    SciTech Connect (OSTI)

    Kesse, Charles E. [PPPL; Kim, S-H. [ITER; Koechl, F. [EURATOM-OAW/ATI

    2014-09-01T23:59:59.000Z

    The entry to burn and flattop burn control in ITER will be a critical need from the first DT experiments. Simulations are used to address time-dependent behavior under a range of possible conditions that include injected power level, impurity content (W, Ar, Be), density evolution, H-mode regimes, controlled parameter (Wth, Pnet, Pfusion), and actuator (Paux, fueling, fAr), with a range of transport models. A number of physics issues at the L-H transition require better understanding to project to ITER, however, simulations indicate viable control with sufficient auxiliary power (up to 73 MW), while lower powers become marginal (as low as 43 MW).

  20. Iterative algorithm for the volume integral method for magnetostatics problems

    SciTech Connect (OSTI)

    Pasciak, J.E.

    1980-11-01T23:59:59.000Z

    Volume integral methods for solving nonlinear magnetostatics problems are considered in this paper. The integral method is discretized by a Galerkin technique. Estimates are given which show that the linearized problems are well conditioned and hence easily solved using iterative techniques. Comparisons of iterative algorithms with the elimination method of GFUN3D shows that the iterative method gives an order of magnitude improvement in computational time as well as memory requirements for large problems. Computational experiments for a test problem as well as a double layer dipole magnet are given. Error estimates for the linearized problem are also derived.

  1. Shattered Pellet Disruption Mitigation Technology Development for ITER

    SciTech Connect (OSTI)

    Baylor, Larry R [ORNL; Combs, Stephen Kirk [ORNL; Jernigan, T. C. [Oak Ridge National Laboratory (ORNL); Meitner, Steven J [ORNL; Edgemon, Timothy D [ORNL; Parks, P. B. [General Atomics; Commaux, Nicolas JC [ORNL; Maruyama, S. [ITER International Team, Garching, Germany; Caughman, John B [ORNL; Rasmussen, David A [ORNL

    2010-01-01T23:59:59.000Z

    The mitigation of first wall thermal and mechanical loads and damage from runaway electrons during disruptions are critical for successful long term operation of ITER. Disruption mitigation tools based on shattered pellet injection are being developed at Oak Ridge National Laboratory that can be employed on ITER to provide the necessary mitigation of thermal and mechanical loads from disruptions as well as provide collisional damping to inhibit the formation of runaway electrons . Here we present progress on the development of the technology to provide reliable disruption mitigation with large shattered cryogenic pellets. An example of how this concept can be employed on ITER is discussed.

  2. IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, VOL. 14, NO. 2, JUNE 2004 1519 Tcs Tests and Performance Assessment of the ITER

    E-Print Network [OSTI]

    Hampshire, Damian

    racetrack coil is wound in double pancakes in the grooves of stainless steel radial plates using dual and Performance Assessment of the ITER Toroidal Field Model Coil (Phase II) R. Zanino, M. Bagnasco, G. Dittrich, W of Forschungszentrum Karlsruhe, Germany: in Phase I, completed in 2001, the coil was tested in its self-field, while

  3. Overlapping local/global iteration framework for whole-core transport solution

    SciTech Connect (OSTI)

    Cho, N. Z.; Yuk, S.; Yoo, H. J.; Yun, S. [Korea Advanced Inst. of Science and Technology KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 (Korea, Republic of)

    2012-07-01T23:59:59.000Z

    In current practice of reactor design analysis, whole-core diffusion nodal method is used in which nodal parameters are provided by single-assembly lattice physics calculation with net current zero boundary condition. Thus, the whole-core solution is not transport, because the inter-assembly transport effect is not incorporated. In this paper, the overlapping local/global iteration framework is described that removes the limitation of the current method. It consists of two-level iterative computations: half-node overlapping local problems embedded in a global problem. The local problem can employ fine-group deterministic or continuous-energy stochastic (Monte Carlo) transport methods, while the global problem is an equivalent coarse-group transport model based on p-CMFD methodology. The method is tested on several highly heterogeneous multi-slab problems with encouraging results. (authors)

  4. Iterative procedure for in-situ EUV optical testing with an incoherent source

    SciTech Connect (OSTI)

    Miyawaka, Ryan; Naulleau, Patrick; Zakhor, Avideh

    2009-12-01T23:59:59.000Z

    We propose an iterative method for in-situ optical testing under partially coherent illumination that relies on the rapid computation of aerial images. In this method a known pattern is imaged with the test optic at several planes through focus. A model is created that iterates through possible aberration maps until the through-focus series of aerial images matches the experimental result. The computation time of calculating the through-focus series is significantly reduced by a-SOCS, an adapted form of the Sum Of Coherent Systems (SOCS) decomposition. In this method, the Hopkins formulation is described by an operator S which maps the space of pupil aberrations to the space of aerial images. This operator is well approximated by a truncated sum of its spectral components.

  5. ITER vacuum vessel design (D201 subtask 1.3 and subtask 3). Final report

    SciTech Connect (OSTI)

    NONE

    1996-08-01T23:59:59.000Z

    ITER Task No. D201, Vacuum Vessel Design (Subtask 1.3 and Subtask 3), was initiated to propose and evaluate local vacuum vessel reinforcement alternatives in proximity to the Neutral Beam, Radial Mid-Plane, Top, and Divertor Ports. These areas were reported to be highly stressed regions based on the results of preliminary stress analyses performed by the USHT (US Home Team) and the ITER Joint Central Team (JCT) at the Garching JWS (Joint Work Site). Initial design activities focused on the divertor port region which was reported to experience the highest stress intensities. Existing stress analysis models and results were reviewed with the USHT stress analysts to obtain an overall understanding of the vessel response to the various applied loads. These reviews indicated that the reported stress intensities in the divertor port region were significantly affected by the loads applied to the vessel in adjacent regions.

  6. Pellet Fueling Technology Development for Efficient Fueling of Burning Plasmas in ITER

    SciTech Connect (OSTI)

    Baylor, Larry R [ORNL; Parks, P. B. [General Atomics; Jernigan, Thomas C [ORNL; Caughman, John B [ORNL; Combs, Stephen Kirk [ORNL; Foust, Charles R [ORNL; Houlberg, Wayne A [ORNL; Maruyama, S. [ITER International Team, Garching, Germany; Rasmussen, David A [ORNL

    2007-01-01T23:59:59.000Z

    Pellet injection from the inner wall is planned for use on ITER as the primary core fueling system since gas fueling is expected to be highly inefficient in burning plasmas. Tests of the inner wall guide tube have shown that 5mm pellets with up to 300 m/s speeds can survive intact and provide the necessary core fueling rate. Modeling and extrapolation of the inner wall pellet injection experiments from today's smaller tokamaks leads to the prediction that this method will provide efficient core fueling beyond the pedestal region. Using pellets for triggering of frequent small edge localized modes is an attractive additional benefit that the pellet injection system can provide. A description of the ITER pellet injection system capabilities for fueling and ELM triggering are presented and performance expectations are discussed.

  7. The ITER 3D Magnetic Diagnostic Response to Applied n=3 and n=4 RMP's

    SciTech Connect (OSTI)

    Lazerson, S A [PPPL

    2014-09-01T23:59:59.000Z

    The ITER magnetic diagnostic response to applied n=3 and n=4 RMPs has been calculated for the 15MA scenario. The VMEC code was utilized to calculate free boundary 3D ideal MHD equilibria, where the non-stellarator symmetric terms were included in the calculation. This allows an assessment to be made of the possible boundary displacements due to RMP application in ITER. As the VMEC code assumes a continuous set of nested flux surface, the possibility of island and stochastic region formation is ignored. At the start of the current at-top (L-Mode) application of n = 4 RMP's indicates approximately 1 cm peak-to-peak displacements on the low field side of the plasma while later in the shot (H-mode) perturbations as large as 3 cm are present. Forward modeling of the ITER magnetic diagnostics indicates significant non-axisymmetric plasma response, exceeding 10% the axisymmetric signal in many of the flux loops. Magnetic #12;field probes seem to indicate a greater robustness to 3D effects but still indicate large sensitivities to 3D effects in a number of sensors. Forward modeling of the diagnostics response to 3D equilibria allows assessment of diagnostics design and control scenarios.

  8. Numerical simulations of welds of thick steel pieces of interest for the thermonuclear fusion ITER machine

    E-Print Network [OSTI]

    Carmignani, B

    2005-01-01T23:59:59.000Z

    Numerical simulations of welds of thick steel pieces of interest for the thermonuclear fusion ITER machine

  9. Inside ITER seminar on History of Fusion Page 1 History of Fusion

    E-Print Network [OSTI]

    Union thermonuclear explosion 400kT #12;Inside ITER seminar on History of Fusion Page 4 Big IvanInside ITER seminar on History of Fusion Page 1 History of Fusion Personal view V. Chuyanov 9 July 2009 Special thanks to ITER Communication Division. #12;Inside ITER seminar on History of Fusion Page 2

  10. From Use Cases of the Joint European Torus towards Integrated Commissioning Requirements of the ITER Tokamak

    E-Print Network [OSTI]

    From Use Cases of the Joint European Torus towards Integrated Commissioning Requirements of the ITER Tokamak

  11. PPPL3246 Preprint: April 1997, UC420 THE PHYSICS ROLE OF ITER

    E-Print Network [OSTI]

    ­scale plasma physics research. First and foremost, experiments in ITER will explore ``controlled ignition

  12. Test blanket modules in ITER: An overview on proposed designs and required DEMO-relevant materials

    E-Print Network [OSTI]

    Abdou, Mohamed

    Test blanket modules in ITER: An overview on proposed designs and required DEMO-relevant materials, Russian Federation Abstract Within the framework of the ITER Test Blanket Working Group, the ITER Parties have made several proposals for test blanket modules to be tested in ITER from the first day of H

  13. ITER: The International Thermonuclear Experimental Reactor and the Nuclear Weapons Proliferation

    E-Print Network [OSTI]

    André Gsponer; Jean-pierre Hurni

    2004-01-01T23:59:59.000Z

    militarytechnical reasons and implications of the very probable siting of ITER (the International Thermonuclear

  14. Exhibit 9RDF Technical Data -ITER UT-B Contracts Div Page 1 of 5

    E-Print Network [OSTI]

    Pennycook, Steve

    Exhibit 9RDF ­ Technical Data - ITER UT-B Contracts Div Sept 2009 Page 1 of 5 ex9rdf-ITER-sept09.doc Exhibit 9RDF-ITER Ref: DEAR 970.5227-1 TECHNICAL DATA ­ ITER (Sept 2009) 1. Rights in Data; (ii) Unlimited rights in Technical Data and Computer Software specifically used in the performa

  15. Plans for U.S. Contributions to ITER

    E-Print Network [OSTI]

    Physics Laboratory (New Jersey) · Electric Power Systems · Diagnostics Savannah River National Laboratory, but co-located U.S. ITER / Sauthoff Slide 4 #12;Oak Ridge National Laboratory (Tennessee), host lab

  16. Revisiting Stopping Rules for Iterative Methods used in Emission Tomography

    E-Print Network [OSTI]

    Renaut, Rosemary

    Stopping Rules for Iterative Methods used in Emission Tomography Hongbin Guo,a, Rosemary A Renautb a Insta.guo@gmail.com (Hongbin Guo) Preprint submitted to Computerized Medical Imaging and Graphics September 28, 2010

  17. A weighted iterative algorithm for neuromagnetic imaging

    SciTech Connect (OSTI)

    Gorodnitsky, I. (Los Alamos National Lab., NM (United States) California Univ., San Diego, La Jolla, CA (United States)); George, J.S.; Schlitt, H.A.; Lewis, P.S. (Los Alamos National Lab., NM (United States))

    1992-01-01T23:59:59.000Z

    The goal of neuromagnetic source reconstruction is high resolution 3-D mapping of the current distribution within the brain. However, the neuromagnetic inverse problem is ill-posed and typically underdetermined. The Moore-Penrose pseudoinverse provides a linear algebraic inverse calculation that simultaneously minimizes chisquare and the Euclidean norm of the component currents. Such minimum norm'' reconstructions tend to produce diffuse and superficial current distributions because voxels nearer the sensor array can account for more power in the data with less current than deeper voxels. We describe an algorithm that overcomes the bias of minimum norm procedures toward superficial solutions by using weights chosen to compensate for the distance dependence of magnetic signal strength. We also apply a Bayesian weighting strategy in an iterative pseudoinverse computation, to address the bias of the linear estimator procedure toward diffuse solutions. This strategy produces a progressively more focal current distribution while accomodating distributed current sources, and appears to effectively reduce the problems associated with the under-determined linear system.

  18. A weighted iterative algorithm for neuromagnetic imaging

    SciTech Connect (OSTI)

    Gorodnitsky, I. [Los Alamos National Lab., NM (United States)]|[California Univ., San Diego, La Jolla, CA (United States); George, J.S.; Schlitt, H.A.; Lewis, P.S. [Los Alamos National Lab., NM (United States)

    1992-09-01T23:59:59.000Z

    The goal of neuromagnetic source reconstruction is high resolution 3-D mapping of the current distribution within the brain. However, the neuromagnetic inverse problem is ill-posed and typically underdetermined. The Moore-Penrose pseudoinverse provides a linear algebraic inverse calculation that simultaneously minimizes chisquare and the Euclidean norm of the component currents. Such ``minimum norm`` reconstructions tend to produce diffuse and superficial current distributions because voxels nearer the sensor array can account for more power in the data with less current than deeper voxels. We describe an algorithm that overcomes the bias of minimum norm procedures toward superficial solutions by using weights chosen to compensate for the distance dependence of magnetic signal strength. We also apply a Bayesian weighting strategy in an iterative pseudoinverse computation, to address the bias of the linear estimator procedure toward diffuse solutions. This strategy produces a progressively more focal current distribution while accomodating distributed current sources, and appears to effectively reduce the problems associated with the under-determined linear system.

  19. Project Manager, U.S. ITER INSIDE: ITER Site Progress Washington

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)IntegratedSpeedingTechnical News,Program DirectionProject ATHENAManagement ProjectITER

  20. Involvement and Communication Committee.

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes | NationalCurriculum IntroductionInvestor andPublic Involvement

  1. Iterative Solution of Elliptic Equations with a Small Parameter

    E-Print Network [OSTI]

    Segatti, Antonio

    and engineering are modelled by partial differ- ential equations involving a small parameter defining a certain are positive semi-definite linear partial differential operators, such that the operator t2 L1 +L0 is coercive the properties of the operators Li and the vectors x and b describe the unknown u and the load f with respect

  2. Development of the Long Pulse Negative Ion Source for ITER

    SciTech Connect (OSTI)

    Hemsworth, R.S.; Svensson, L.; Esch, H.P.L. de; Krylov, A.; Massmann, P. [Association EURATOM-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 St Paul-lez-Durance (France); Boilson, D. [Association EURATOM-DCU, PRL/NCPST, Glasnevin, Dublin 13 (Ireland); Fanz, U. [Association EURATOM-IPP, Max-Planck-Institut fuer Plasmaphysik D-85748 Garching (Germany); Zaniol, B. [CONSORZIO RFX Association EURATOM-ENEA, Corso Stati Uniti 4, I-35127 Padova (Italy)

    2005-04-06T23:59:59.000Z

    A model of the ion source designed for the neutral beam injectors of the International Thermonuclear Experimental Reactor (ITER), the KAMABOKO III ion source, is being tested on the MANTIS test stand at the DRFC Cadarache in collaboration with JAERI, Japan, who designed and supplied the ion source. The ion source is attached to a 3 grid 30 keV accelerator (also supplied by JAERI) and the accelerated negative ion current is determined from the energy deposited on a calorimeter located 1.6 m from the source.During experiments on MANTIS three adverse effects of long pulse operation were found: The negative ion current to the calorimeter is {approx_equal}50% of that obtained from short pulse operation Increasing the plasma grid (PG) temperature results in {<=}40% enhancement in negative ion yield, substantially below that reported for short pulse operation, {>=}100%. The caesium 'consumption' is up to 1500 times that expected.Results presented here indicate that each of these is, at least partially, explained by thermal effects. Additionally presented are the results of a detailed characterisation of the source, which enable the most efficient mode of operation to be identified.

  3. Recent progress on lower hybrid current drive and implications for ITER

    E-Print Network [OSTI]

    Hillairet, Julien; Goniche, M; Achard, J; Armitano, A; Beckett, B; Belo, J; Berger-By, G; Corbel, E; Delpech, L; Decker, J; Dumont, R; Guilhem, D; Kazarian, F; Litaudon, X; Magne, R; Marfisi, L; Mollard, P; Namkung, W; Nilsson, E; Park, S; Peysson, Y; Preynas, M; Sharma, P K; Prou, M

    2015-01-01T23:59:59.000Z

    The sustainment of steady-state plasmas in tokamaks requires efficient current drive systems. Lower Hybrid Current Drive (LHCD) is currently the most efficient method to generate a continuous additional off-axis toroidal plasma current as well as reduce the poloidal flux consumption during the plasma current ramp-up phase. The operation of the Tore Supra ITER-like LH launcher has demonstrated the capability to couple LH power at ITER-like power densities with very low reflected power during long pulses. In addition, the installation of eight 700kW/CW klystrons at the LH transmitter has allowed increasing the total LH power in long pulse scenarios. However, in order to achieve pure stationary LH sustained plasmas, some R\\&D are needed to increase the reliability of all the systems and codes, from the RF sources to the plasma scenario prediction. The CEA/IRFM is addressing some of these issues by leading a R\\&D program towards an ITER LH system and by the validation of an integrated LH modeling suite of...

  4. Electrostatic Dust Detection and Removal for ITER

    SciTech Connect (OSTI)

    C.H. Skinner; A. Campos; H. Kugel; J. Leisure; A.L. Roquemore; S. Wagner

    2008-09-01T23:59:59.000Z

    We present some recent results on two innovative applications of microelectronics technology to dust inventory measurement and dust removal in ITER. A novel device to detect the settling of dust particles on a remote surface has been developed in the laboratory. A circuit board with a grid of two interlocking conductive traces with 25 ?m spacing is biased to 30 – 50 V. Carbon particles landing on the energized grid create a transient short circuit. The current flowing through the short circuit creates a voltage pulse that is recorded by standard nuclear counting electronics and the total number of counts is related to the mass of dust impinging on the grid. The particles typically vaporize in a few seconds restoring the previous voltage standoff. Experience on NSTX however, showed that in a tokamak environment it was still possible for large particles or fibers to remain on the grid causing a long term short circuit. We report on the development of a gas puff system that uses helium to clear such particles. Experiments with varying nozzle designs, backing pressures, puff durations, and exit flow orientations have given an optimal configuration that effectively removes particles from an area up to 25 cm² with a single nozzle. In a separate experiment we are developing an advanced circuit grid of three interlocking traces that can generate a miniature electrostatic traveling wave for transporting dust to a suitable exit port. We have fabricated such a 3-pole circuit board with 25 micron insulated traces that operates with voltages up to 200 V. Recent results showed motion of dust particles with the application of only 50 V bias voltage. Such a device could potentially remove dust continuously without dedicated interventions and without loss of machine availability for plasma operations.

  5. Recursive Programming Model for Crop Production on the Texas High Plains

    E-Print Network [OSTI]

    Reneau, D. R.; Lacewell, R. D.; Ellis, J. R.

    , the model will loop through up to 20 iterations, rebuilding the LP matrix for each iteration and writing a report for each period. The feedback section of the recursive model is used to update the groundwater situation after solution of each iteration...

  6. Power Handling in ITER: Divertor and Blanket Design and R&D M. Merola 1), D. Loesser 2), R. Raffray 1) on behalf of the ITER Organization, ITER

    E-Print Network [OSTI]

    Raffray, A. René

    the thermonuclear plasma and cover an area of about 850 m2 . The main function of the divertor is minimizing the thermonuclear plasma. One of the most technically challenging components of the ITER machine are plasma-facing components (PFCs), which directly face the thermonuclear plasma and cover an area of about 850 m2

  7. ITER physics design guidelines at high aspect ratio

    SciTech Connect (OSTI)

    Uckan, N.A.

    1991-01-01T23:59:59.000Z

    The physics requirements for ITER design are formulated in a set of physics design guidelines. These guidelines, established by the ITER Physics Group during the Conceptual Design Activity (CDA, 1988--90), were based on credible extrapolations of the tokamak physics database as assessed during the CDA, and defined a class of tokamak designs (with plasma current I {approximately}20 MA and aspect ratio A {approximately}2.5--3.5) that meet the ITER objectives. Recent US studies have indicated that there may be significant benefits if the ITER-CDA design point is moved from the low aspect ratio, high current baseline (A = 2.79, I = 22 MA) to a high aspect ratio machine at A {approximately}4, I {approximately}15 MA, especially regarding steady-state, technology-testing performance. To adequately assess the physics and technology testing capability of higher aspect ratio design options, several changes are proposed to the original ITER guidelines to reflect the latest (although limited) developments in physics understanding at higher aspect ratios. The critical issues for higher aspect ratio design options are the uncertainty in scaling of confinement with aspect ratio, the variation of vertical stability with elongation and aspect ratio, plasma shaping requirements, ability to control and maintain plasma current and q-profiles for MHD stability (and volt-second consumption), access for current drive, restrictions on field ripple and divertor plate incident angles, etc. 5 refs., 1 tab.

  8. Description of the prototype diagnostic residual gas analyzer for ITER

    SciTech Connect (OSTI)

    Younkin, T. R., E-mail: tyounkin@gatech.edu [Fusion and Materials for Nuclear Systems Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6169 (United States); Georgia Institute of Technology, Woodruff School of Mechanical Engineering – Nuclear and Radiological Engineering Program, Atlanta, Georgia 30332 (United States); Biewer, T. M.; Klepper, C. C.; Marcus, C. [Fusion and Materials for Nuclear Systems Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6169 (United States)

    2014-11-15T23:59:59.000Z

    The diagnostic residual gas analyzer (DRGA) system to be used during ITER tokamak operation is being designed at Oak Ridge National Laboratory to measure fuel ratios (deuterium and tritium), fusion ash (helium), and impurities in the plasma. The eventual purpose of this instrument is for machine protection, basic control, and physics on ITER. Prototyping is ongoing to optimize the hardware setup and measurement capabilities. The DRGA prototype is comprised of a vacuum system and measurement technologies that will overlap to meet ITER measurement requirements. Three technologies included in this diagnostic are a quadrupole mass spectrometer, an ion trap mass spectrometer, and an optical penning gauge that are designed to document relative and absolute gas concentrations.

  9. Diamond neutral particle spectrometer for fusion reactor ITER

    SciTech Connect (OSTI)

    Krasilnikov, V.; Amosov, V.; Kaschuck, Yu.; Skopintsev, D. [Institution PROJECT CENTER ITER, 1, Akademik Kurchatov Sq., Moscow (Russian Federation)

    2014-08-21T23:59:59.000Z

    A compact diamond neutral particle spectrometer with digital signal processing has been developed for fast charge-exchange atoms and neutrons measurements at ITER fusion reactor conditions. This spectrometer will play supplementary role for Neutral Particle Analyzer providing 10 ms time and 30 keV energy resolutions for fast particle spectra in non-tritium ITER phase. These data will also be implemented for independent studies of fast ions distribution function evolution in various plasma scenarios with the formation of a single fraction of high-energy ions. In tritium ITER phase the DNPS will measure 14 MeV neutrons spectra. The spectrometer with digital signal processing can operate at peak counting rates reaching a value of 10{sup 6} cps. Diamond neutral particle spectrometer is applicable to future fusion reactors due to its high radiation hardness, fast response and high energy resolution.

  10. Fusion Materials Science and Technology Research Needs: Now and During the ITER era

    SciTech Connect (OSTI)

    Wirth, Brian D.; Kurtz, Richard J.; Snead, Lance L.

    2013-09-30T23:59:59.000Z

    The plasma facing components, first wall and blanket systems of future tokamak-based fusion power plants arguably represent the single greatest materials engineering challenge of all time. Indeed, the United States National Academy of Engineering has recently ranked the quest for fusion as one of the top grand challenges for engineering in the 21st Century. These challenges are even more pronounced by the lack of experimental testing facilities that replicate the extreme operating environment involving simultaneous high heat and particle fluxes, large time varying stresses, corrosive chemical environments, and large fluxes of 14-MeV peaked fusion neutrons. This paper will review, and attempt to prioritize, the materials research and development challenges facing fusion nuclear science and technology into the ITER era and beyond to DEMO. In particular, the presentation will highlight the materials degradation mechanisms we anticipate to occur in the fusion environment, the temperature- displacement goals for fusion materials and plasma facing components and the near and long-term materials challenges required for both ITER, a fusion nuclear science facility and longer term ultimately DEMO.

  11. A PRELIMINARY ASSESSMENT OF THE OCCUPATIONAL RADIATION EXPOSURE FROM MAINTAINING THE US ITER DCLL TBM

    SciTech Connect (OSTI)

    B. J. Merrill; L. C. Cadwallader; M. Dagher

    2008-09-01T23:59:59.000Z

    This paper details an Occupational Radiation Exposure (ORE) analysis performed for the US International Thermonuclear Experimental Reactor (ITER) Dual Coolant Lead Lithium (DCLL) Test Blanket Module (TBM). This ORE analysis was performed with the QADMOD dose code for maintenance activities anticipated for the US DCLL TBM concept and its ancillary systems. Identification of the maintenance tasks that will have to be performed and estimates of the time required to perform these tasks were developed based on either expert opinion or on industrial maintenance experience for similar technologies. This paper details the modeling activity and the calculated doses for the maintenance activities envisioned for the US DCLL TBM.

  12. Testability of non-autonomous two dimensional iterative logic array

    E-Print Network [OSTI]

    Nagumo, Hideo

    1991-01-01T23:59:59.000Z

    ' SCIENCE August III91 Major Subject: Electrical Engineering TESTABILITY OF NON-AUTONOMOUS T'A'0 DIMENSIONAL ITERATIVE LOGIC ARRAY A Thesis by HIDEO NAGUMO Approved as to style and content by: . . ed~ I(aran L. watson (Chair of Committee) Mi Lu... (Member) William G. Bliss (Member) Donald K. Friesen (Member) Jo Howze (Head of Department) August 1991 ABSTRACT Testability of i%on-Autonomous Two-Dimensional Iterative Logic Array. (August 1991) Hideo iX'agumo, B. S. , Shinshu University...

  13. Bragg x-ray survey spectrometer for ITER

    SciTech Connect (OSTI)

    Varshney, S. K.; Jakhar, S. [ITER-India, Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428 (India); Barnsley, R. [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France); O'Mullane, M. G. [Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom)

    2012-10-15T23:59:59.000Z

    Several potential impurity ions in the ITER plasmas will lead to loss of confined energy through line and continuum emission. For real time monitoring of impurities, a seven channel Bragg x-ray spectrometer (XRCS survey) is considered. This paper presents design and analysis of the spectrometer, including x-ray tracing by the Shadow-XOP code, sensitivity calculations for reference H-mode plasma and neutronics assessment. The XRCS survey performance analysis shows that the ITER measurement requirements of impurity monitoring in 10 ms integration time at the minimum levels for low-Z to high-Z impurity ions can largely be met.

  14. Iterative methods for solving nonlinear problems of nuclear reactor criticality

    SciTech Connect (OSTI)

    Kuz'min, A. M., E-mail: mephi.kam@mail.ru [National Research Nuclear University MEPhI (Russian Federation)

    2012-12-15T23:59:59.000Z

    The paper presents iterative methods for calculating the neutron flux distribution in nonlinear problems of nuclear reactor criticality. Algorithms for solving equations for variations in the neutron flux are considered. Convergence of the iterative processes is studied for two nonlinear problems in which macroscopic interaction cross sections are functionals of the spatial neutron distribution. In the first problem, the neutron flux distribution depends on the water coolant density, and in the second one, it depends on the fuel temperature. Simple relationships connecting the vapor content and the temperature with the neutron flux are used.

  15. Helium-cooled lithiuim compound suspension blanket concept for ITER

    SciTech Connect (OSTI)

    Gohar, Y.; Baker, C.C.; Attaya, H.; Billone, M.; Clemmer, R.C.; Finn, P.A.; Hassanein, A.; Johnson, C.E.; Majumdar, S.; Mattas, R.F.

    1988-08-01T23:59:59.000Z

    This blanket concept uses a dilute suspension of fine solid breeder particles (Li/sub 2/O, LiAlO/sub 2/, or Li/sub 4/SiO/sub 4/) in a carrier gas (He) as the coolant and the tritium breeding stream. A small fraction of this stream is processed outside the reactor for tritium recovery. The blanket consists of a beryllium multiplier and carbon/steel reflector. A steel clad is used for all materials. A carbon reflector is employed to reduce the beryllium thickness used in the blanket for a specific tritium breeding ratio. The breeder particle size has to exceed few microns (greater than or equal to2 microns) to avoid sticking problems on the cold surfaces of the heat exchanger. The helium gas pressure is in the range of 2 to 3 MPa to carry the blanket and the heat exchanger loop. The solid breeder concentration in the helium stream is 1 to 5 volume percent. A high lithium-6 enrichment is used to produce a high tritium breeding ratio and to reduce the breeder concentration in the helium gas. At a lithium-6 enrichment of 90%, the local tritium breeding ratio is 2.03 based on a one-dimensional poloidal model. The total thickness of the helium stream is only 4 cm out of the 50 cm total blanket thickness. The blanket uses a 35 cm of beryllium for neutron multiplication. A simple multi-layer design is employed where the blanket sector has the helium coolant flowing in the poloidal direction. The blanket concept has several unique advantages which are very beneficial for fusion reactors including ITER. 10 refs., 2 tabs.

  16. Impacts of pellets injected from the low-field side on plasma in ITER

    SciTech Connect (OSTI)

    Wisitsorasak, A. [Mahidol University, Faculty of Science (Thailand); Onjun, T. [Thammasat University, School of Manufacturing Systems and Mechanical Engineering, Sirindhorn International Institute of Technology (Thailand)

    2011-01-15T23:59:59.000Z

    Impacts of pellets injected from the low-field side (LFS) on plasma in ITER are investigated using the 1.5D BALDUR integrated predictive modeling code. In these simulations, the pellet ablation is described using the neutral gas shielding (NGS) model. The pellet ablation model is coupled with the plasma core transport model, which is a combination of the MMM95 anomalous transport model and NCLASS neoclassical transport model. The boundary conditions are assumed to be at the top of the pedestal, in which the pedestal parameters are predicted using a pedestal model based on the theoretical-based pedestal width scaling (either magnetic and flow shear stabilization width scaling, or flow shear stabilization width scaling, or normalized poloidal pressure width scaling) and the infinite-n ballooning mode pressure gradient limit. These pedestal models depend sensitively on the density at the top of the pedestal, which can be strongly influenced by the injection of pellets. The combination of the MMM95 and NCLASS models, together with the pedestal and NGS models, is used to simulate the time evolution of the plasma current, ion and electron temperatures, and density profiles for ITER standard type-I ELMy H-mode discharges during the injection of LFS pellets. It is found that the injection of pellets results in a complicated plasma scenario, especially in the outer region of the plasma and the plasma conditions at the boundary in which the pellet has an impact on increasing the plasma edge density, but reducing the plasma edge temperature. The LFS pellet has a stronger impact on the edge as compared to the center. For fusion performance, the pellet can result in either enhancement or degradation, depending sensitively on the pellet parameters; such as the pellet size, pellet velocity, and pellet frequency. For example, when a series of deuterium pellets with a size of 0.5 cm, velocity of 1 km/s, and frequency of 2 Hz are injected into the ITER plasma from the LFS, the plasma performance, evaluated in terms of Q{sub fusion}, can increase to 72% of that before the use of pellets. It is also found that the injection of pellets results in an increase in the ion and electron densities, but does not enhance the central plasma density. On the other hand, it results in the formation of another peak of the plasma density in the outer region near the plasma edge. The formation of the density peak results in the reduction of plasma transports near the edge by decreasing the contributions of ion-temperature-gradient and trapped electron modes, as well as kinetic ballooning modes.

  17. active user involvement: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    architecture. DBS was implemented on the Nano-Threads Programming Model (NPM) as part of NANOS, a large-scale project involving the development of a runtime...

  18. Perspectives on US program support of FNSF and ITER in coming decade

    E-Print Network [OSTI]

    -pulse PMI, stellarator) · U.S. Burning Plasma Organization could also expand beyond ITER to incorporate FNSP facility support a staged approach? (PMI FNSF CTF Pilot?) · Which ITER physics and technology can

  19. Brussels advocates a lone rider for ITER 09/22/2004 Edition

    E-Print Network [OSTI]

    can advance alone to establish the thermonuclear reactor experimental ITER in Cadarache. France in the construction of the future experimental thermonuclear reactor ITER, if Brussels does not manage to convince

  20. Advances in the Understanding of ELM Suppression by Resonant Magnetic Perturbations (RMPs) in DIII-D and Implications for ITER

    SciTech Connect (OSTI)

    Nazikian, R. [PPPL

    2014-09-01T23:59:59.000Z

    Experiments on DIII-D have expanding the operating window for RMP ELM suppression to higher q95 with dominant electron heating and fully non-inductive current drive relevant to advanced modes of ITER operation. Robust ELM suppression has also been obtained with a reduced coil set, mitigating the risk of coil failure in maintaining ELM suppression in ITER. These results significantly expand the operating space and reduce risk for obtaining RMP ELM suppression in ITER. Efforts have also been made to search for 3D cause of ELM suppression. No internal non-axisymmetric structure is detected at the top of the pedestal, indicating that the dominant effect of the RMP is to produce an n=0 transport modification of the profiles. Linear two fluid MHD simulations using M3D-C1 indicate resonant field penetration and significant magnetic stochasticity at the top of the pedestal, consistent with the absence of detectable 3D structure in that region. A profile database was developed to compare the scaling of the pedestal and global confinement with the applied 3D field strength in ELM suppressed and ELM mitigated plasmas. The EPED pedestal model accurately predicts the measured pedestal pressure at the threshold of ELM suppression, increasing confidence in theoretical projections to ITER pedestal conditions. Both the H-factor (H(sub)98y2) and thermal energy confinement time do not degrade substantially with applied RMP fields near the threshold of ELM suppression, enhancing confidence in the compatibility of ITER high performance operation with RMP ELM suppression.

  1. PPPL-3246 -Preprint: April 1997, UC-420 THE PHYSICS ROLE OF ITER

    E-Print Network [OSTI]

    . INTRODUCTION The ITER plasma will provide a unique opportunity for reactor-scale plasma physics research. First

  2. Exhibit 9 Technical Data ITER UT-B Contracts Div Page 1 of 5

    E-Print Network [OSTI]

    Pennycook, Steve

    Exhibit 9 ­ Technical Data ­ ITER UT-B Contracts Div June 2011 Page 1 of 5 ex9-ITER-june11.doc Exhibit 9 ITER Ref: DEAR 927.409; FAR 52.227-14, 52.227-14 Alt.V, 52.227-16 TECHNICAL DATA - ITER (June, or statements, regardless of the media in which recorded, that allow or cause a computer to perform a specific

  3. Iterative Detection and Channel Estimation for Thomas Zemen

    E-Print Network [OSTI]

    Müller, Ralf R.

    Iterative Detection and Channel Estimation for MC­CDMA Thomas Zemen Siemens Austria, PSE PRO RCD ErdbergerlË?ande 26 A­1031 Vienna, Austria E­mail: thomas.zemen@siemens.com Joachim Wehinger, Christoph wireless communication systems. Their equalization is based on the fast Fourier transform, allowing

  4. Iterative Detection and Channel Estimation for Thomas Zemen

    E-Print Network [OSTI]

    Zemen, Thomas

    Iterative Detection and Channel Estimation for MC-CDMA Thomas Zemen Siemens Austria, PSE PRO RCD Erdbergerl¨ande 26 A-1031 Vienna, Austria E-mail: thomas.zemen@siemens.com Joachim Wehinger, Christoph communication systems. Their equalization is based on the fast Fourier transform, allowing for an efficient

  5. PUBLISHED VERSION RF contact development for the ITER ICRH antenna

    E-Print Network [OSTI]

    Cyclotron (IC) antenna design, ITER Organization requested qualification tests on sliding Radio contacts in relevant conditions (2.25kA @ 62.5MHz, vacuum pressure detailed with RF power tests for long shot duration (1000s) under vacuum and extensive sliding tests

  6. Enantioselective Total Synthesis of (-)-Pironetin: Iterative Aldol Reactions

    E-Print Network [OSTI]

    titanium mediated iterative aldol reactions. Key steps in this synthesis include an acetal aldol reaction to establish the stereochemistry at C8 and C9, an acetate aldol reaction, and "Evans" syn aldol reaction and allylation methods,4m Enders and co-workers have disclosed a convergent total synthesis relying on RAMP

  7. Analysis of Disruption Scenarios Their Possible Mitigation in ITER

    E-Print Network [OSTI]

    of the design) - Database analysis and physics guidelines for current quench rate and halo current - Simulation [MA/m2 ] Te=2eV Te=5eV Te=8eV ITER 9 MA 24 MA =0.72 m-3 #12;· Good measure for quench time

  8. Sabina Griffith Email: Sabina.Griffith@iter.org

    E-Print Network [OSTI]

    Energy Agency (IAEA). In recognition of his life-long contribution to ITER, a moment of silence was approved at the extraordinary IC on July 28, 2010. This report included a new strategy for cost savings with representatives of the local communities, were invited to celebrate the official start of construction

  9. Industrial opportunities on the International Thermonuclear Experimental Reactor (ITER) project

    SciTech Connect (OSTI)

    Ellis, W.R. [Raytheon Engineers and Constructors, New York, NY (United States)

    1996-12-01T23:59:59.000Z

    Industry has been a long-term contributor to the magnetic fusion program, playing a variety of important roles over the years. Manufacturing firms, engineering-construction companies, and the electric utility industry should all be regarded as legitimate stakeholders in the fusion energy program. In a program focused primarily on energy production, industry`s future roles should follow in a natural way, leading to the commercialization of the technology. In a program focused primarily on science and technology, industry`s roles, in the near term, should be, in addition to operating existing research facilities, largely devoted to providing industrial support to the International Thermonuclear Experimental Reactor (ITER) Project. Industrial opportunities on the ITER Project will be guided by the amount of funding available to magnetic fusion generally, since ITER is funded as a component of that program. The ITER Project can conveniently be discussed in terms of its phases, namely, the present Engineering Design Activities (EDA) phase, and the future (as yet not approved) construction phase. 2 refs., 3 tabs.

  10. Overview of Recent Developments in Pellet Injection for ITER

    SciTech Connect (OSTI)

    Combs, Stephen Kirk [ORNL; Baylor, Larry R [ORNL; Meitner, Steven J [ORNL; Caughman, John B [ORNL; Rasmussen, David A [ORNL; Maruyama, So [ITER Organization, Cadarache, France

    2012-01-01T23:59:59.000Z

    Pellet injection is the primary fueling technique planned for core fueling of ITER burning plasmas. Also, the injection of relatively small pellets to purposely trigger rapid small edge localized modes (ELMs) has been proposed as a possible solution to the heat flux damage from larger natural ELMs likely to be an issue on the ITER divertor surfaces. The ITER pellet injection system is designed to inject pellets into the plasma through both inner and outer wall guide tubes. The inner wall guide tubes will provide high throughput pellet fueling while the outerwall guide tubes will be used primarily to trigger ELMs at a high frequency (>15 Hz). The pellet fueling rate ofeach injector is to be up to 120 Pa-m3/s, which will require the formation of solid D-T at a volumetric rate of ~1500 mm3/s. Two injectors are to be provided for ITER at the startup with a provision for up to six injectorsduring the D-T phase. The required throughput of each injector is greater than that of any injector built to date, and a novel twin-screw continuous extrusion system is being developed to meet the challenging design parameters. Status of the development activities will be presented, highlighting recent progress.

  11. Moldable Parallel Job Scheduling Using Job Efficiency: An Iterative Approach

    E-Print Network [OSTI]

    Feitelson, Dror

    Moldable Parallel Job Scheduling Using Job Efficiency: An Iterative Approach Gerald Sabin, Matthew OH 43201, USA, {sabin, langma, saday}@cse.ohio-state.edu Abstract. Currently, job schedulers require "rigid" job submissions from users, who must specify a particular number of processors for each paral

  12. "Enhancing iterative solution methods for general FEM computations using rigid body modes."

    E-Print Network [OSTI]

    Vuik, Kees

    Structures Geomechanics Enhancing iterative solvers in Diana June 27, 2014 5 #12;Finite elements applications Structures Geomechanics Dams and dikes Enhancing iterative solvers in Diana June 27, 2014 5 #12;Finite elements applications Structures Geomechanics Dams and dikes Tunneling Enhancing iterative solvers in Diana

  13. ITER & Fusion Research Reference: MEMO/10/165 Date: 05/05/2010

    E-Print Network [OSTI]

    ITER & Fusion Research Reference: MEMO/10/165 Date: 05/05/2010 HTML: EN PDF: EN DOC: EN MEMO/10/165 Brussels, 5th May 2010 ITER & Fusion Research The Commission has adopted a Communication to the European for International Thermonuclear Experimental Reactor (ITER), which have more than doubled the costs for Europe (to

  14. ASSESSMENT OF THE DCLL TBM THERMOSTRUCTURAL RESPONSE BASED ON ITER DESIGN CRITERIA

    E-Print Network [OSTI]

    Ghoniem, Nasr M.

    codes (e.g., ASME Code4 and RCC-MR5 ). A detailed thermo-structural analysis of the DCLL TBM as safety important ITER components, they must fulfill all required ITER codes and standards for reliable performance under ITER normal operating conditions. II. DESIGN CODE PURPOSE The primary purpose of structural

  15. Annual Report of the EURATOM/CCFE Fusion Programme 2011/12 8 ITER Systems

    E-Print Network [OSTI]

    and undertake leading or major roles in the design and R&D of ITER specialist systems (Heating, Diagnostics and Remote Handling etc.) in Europe; 8ITERSystems · Seek to play other design roles in R&D of ITER specialist its substantial role in the following key ITER systems: · Ion Cyclotron Resonance Heating (ICRH

  16. The Role of the Inner Product in Stopping Criteria for Conjugate Gradient Iterations

    E-Print Network [OSTI]

    Holst, Michael J.

    stopping criteria are derived for conjugate gradient (CG) methods, based on iteration parameters criteria, conjugate gradient methods, B-normal matrices 1 Introduction Unlike a direct method, an iterative1 The Role of the Inner Product in Stopping Criteria for Conjugate Gradient Iterations S. F. Ashby

  17. Innovation is Key from ITER to DEMO M. Porkolab, L. Bromberg, M. Greenwald, A. Hubbard,

    E-Print Network [OSTI]

    PMI in tokamak · SS current drive & heating · Divertor solution compatible with core Porkolab_FPA_2013 #12;For PMI, the step from ITER to DEMO will be enormous. ITER ARIES- ACT1 ARIES- ACT2 R(m) 6.2 6.25 9/R than ITER Factor of 105 increase in pulse length Innovative solutions to critical PMI challenges

  18. A turbulent transport network model in MULTIFLUX coupled with TOUGH2

    SciTech Connect (OSTI)

    Danko, G.; Bahrami, D.; Birkholzer, J.T.

    2011-02-15T23:59:59.000Z

    A new numerical method is described for the fully iterated, conjugate solution of two discrete submodels, involving (a) a transport network model for heat, moisture, and airflows in a high-permeability, air-filled cavity; and (b) a variably saturated fractured porous medium. The transport network submodel is an integrated-parameter, computational fluid dynamics solver, describing the thermal-hydrologic transport processes in the flow channel system of the cavity with laminar or turbulent flow and convective heat and mass transport, using MULTIFLUX. The porous medium submodel, using TOUGH2, is a solver for the heat and mass transport in the fractured rock mass. The new model solution extends the application fields of TOUGH2 by integrating it with turbulent flow and transport in a discrete flow network system. We present demonstrational results for a nuclear waste repository application at Yucca Mountain with the most realistic model assumptions and input parameters including the geometrical layout of the nuclear spent fuel and waste with variable heat load for the individual containers. The MULTIFLUX and TOUGH2 model elements are fully iterated, applying a programmed reprocessing of the Numerical Transport Code Functionalization model-element in an automated Outside Balance Iteration loop. The natural, convective airflow field and the heat and mass transport in a representative emplacement drift during postclosure are explicitly solved in the new model. The results demonstrate that the direction and magnitude of the air circulation patterns and all transport modes are strongly affected by the heat and moisture transport processes in the surrounding rock, justifying the need for a coupled, fully iterated model solution such as the one presented in the paper.

  19. Senate panel orders US withdrawal from ITER Appropriators cite rising costs and mismanagement for terminating US participation in ITER, but

    E-Print Network [OSTI]

    for terminating US participation in ITER, but House spending bill would increase funding above administration is stifling research, science board warns Senate appropriators approved a bill last week that would order by the subcommittee on energy and water development, would allow just $75 million to pay for contracts that have

  20. Information-theoretic discrepancy based iterative reconstructions (IDIR) for polychromatic x-ray tomography

    SciTech Connect (OSTI)

    Jang, Kwang Eun; Lee, Jongha; Sung, Younghun; Lee, SeongDeok [Advanced Media Laboratory, Samsung Advanced Institute of Technology (SAIT), San 14, Nongseo Dong, Giheung Gu, Yongin, Gyeonggi 446-712 (Korea, Republic of)] [Advanced Media Laboratory, Samsung Advanced Institute of Technology (SAIT), San 14, Nongseo Dong, Giheung Gu, Yongin, Gyeonggi 446-712 (Korea, Republic of)

    2013-09-15T23:59:59.000Z

    Purpose: X-ray photons generated from a typical x-ray source for clinical applications exhibit a broad range of wavelengths, and the interactions between individual particles and biological substances depend on particles' energy levels. Most existing reconstruction methods for transmission tomography, however, neglect this polychromatic nature of measurements and rely on the monochromatic approximation. In this study, we developed a new family of iterative methods that incorporates the exact polychromatic model into tomographic image recovery, which improves the accuracy and quality of reconstruction.Methods: The generalized information-theoretic discrepancy (GID) was employed as a new metric for quantifying the distance between the measured and synthetic data. By using special features of the GID, the objective function for polychromatic reconstruction which contains a double integral over the wavelength and the trajectory of incident x-rays was simplified to a paraboloidal form without using the monochromatic approximation. More specifically, the original GID was replaced with a surrogate function with two auxiliary, energy-dependent variables. Subsequently, the alternating minimization technique was applied to solve the double minimization problem. Based on the optimization transfer principle, the objective function was further simplified to the paraboloidal equation, which leads to a closed-form update formula. Numerical experiments on the beam-hardening correction and material-selective reconstruction were conducted to compare and assess the performance of conventional methods and the proposed algorithms.Results: The authors found that the GID determines the distance between its two arguments in a flexible manner. In this study, three groups of GIDs with distinct data representations were considered. The authors demonstrated that one type of GIDs that comprises “raw” data can be viewed as an extension of existing statistical reconstructions; under a particular condition, the GID is equivalent to the Poisson log-likelihood function. The newly proposed GIDs of the other two categories consist of log-transformed measurements, which have the advantage of imposing linearized penalties over multiple discrepancies. For all proposed variants of the GID, the aforementioned strategy was used to obtain a closed-form update equation. Even though it is based on the exact polychromatic model, the derived algorithm bears a structural resemblance to conventional methods based on the monochromatic approximation. The authors named the proposed approach as information-theoretic discrepancy based iterative reconstructions (IDIR). In numerical experiments, IDIR with raw data converged faster than previously known statistical reconstruction methods. IDIR with log-transformed data exhibited superior reconstruction quality and faster convergence speed compared with conventional methods and their variants.Conclusions: The authors' new framework for tomographic reconstruction allows iterative inversion of the polychromatic data model. The primary departure from the traditional iterative reconstruction was the employment of the GID as a new metric for quantifying the inconsistency between the measured and synthetic data. The proposed methods outperformed not only conventional methods based on the monochromatic approximation but also those based on the polychromatic model. The authors have observed that the GID is a very flexible means to design an objective function for iterative reconstructions. Hence, the authors expect that the proposed IDIR framework will also be applicable to other challenging tasks.

  1. An Overview of US ITER Test Blanket Module Program

    SciTech Connect (OSTI)

    Ying, A.; Abdou, Mohamed A.; Wong, Clement; Malang, S.; Morley, Neil B.; Sawan, M.; Merrill, Brad; Sze, Dai Kai; Kurtz, Richard J.; Willms, Scott; Ulrickson, Mike; Zinkle, Steven J.

    2006-01-01T23:59:59.000Z

    A testing strategy and corresponding test plan have been presented for the two proposed US candidate breeder blankets: 1) a helium-cooled solid breeder concept with ferritic steel structure and Be neutron multiplier, but without a fully independent TBM, and 2) a dual-coolant helium-cooled ferritic steel structure with self-cooled LiPb breeding zone that uses a flow channel insert as MHD and thermal insulator. Example test module designs, and configuration choices for each line of ITER TBM are shown and discussed in the paper. In addition, near-term R&D items for decision-making on testing of both solid breeder and dual-coolant PbLi liquid breeder blanket concepts in ITER are identified.

  2. Iterative Entanglement Distillation: Approaching full Elimination of Decoherence

    E-Print Network [OSTI]

    Boris Hage; Aiko Samblowski; James DiGuglielmo; Jaromír Fiurášek; Roman Schnabel

    2010-07-09T23:59:59.000Z

    The distribution and processing of quantum entanglement form the basis of quantum communication and quantum computing. The realization of the two is difficult because quantum information inherently has a high susceptibility to decoherence, i.e. to uncontrollable information loss to the environment. For entanglement distribution, a proposed solution to this problem is capable of fully eliminating decoherence; namely iterative entanglement distillation. This approach builds on a large number of distillation steps each of which extracts a number of weakly decohered entangled states from a larger number of strongly decohered states. Here, for the first time, we experimentally demonstrate iterative distillation of entanglement. Already distilled entangled states were further improved in a second distillation step and also made available for subsequent steps.Our experiment displays the realization of the building blocks required for an entanglement distillation scheme that can fully eliminate decoherence.

  3. Krylov subspace iteration for eigenvalue response matrix calculations

    SciTech Connect (OSTI)

    Roberts, J. A.; Forget, B. [Massachusetts Inst. of Technology, 77 Massachusetts Ave., Cambridge, MA 02141 (United States)

    2012-07-01T23:59:59.000Z

    Recent work has revisited the eigenvalue response matrix method as an approach for reactor core analyses. In its most straightforward form, the method consists of a two-level Eigen problem. An outer Picard iteration updates the k-eigenvalue, while the inner Eigen problem imposes current continuity between coarse meshes. In this paper, several Eigen solvers are evaluated for this inner problem, using several 2-D diffusion benchmarks as test cases. The results indicate both the explicitly-restarted Arnoldi and the Krylov-Schur methods are up to an order of magnitude more efficient than power iteration. This increased efficiency makes the nested eigenvalue formulation more effective than the ILU-preconditioned Newton-Krylov formulation previously studied. (authors)

  4. Water-cooled solid-breeder blanket concept for ITER

    SciTech Connect (OSTI)

    Gohar, Y.; Baker, C.C.; Attaya, H.; Billone, M.; Clemmer, R.C.; Finn, P.A.; Hassanein, A.; Johnson, C.E.; Majumdar, S.; Mattas, R.F.

    1989-03-01T23:59:59.000Z

    A water cooled solid-breeder blanket concept was developed for ITER. The main function of this blanket is to produce the necessary tritium for the ITER operation. Several design features are incorporated in this blanket concept to increase its attractiveness. The main features are the following: (a) a multilayer concept which reduces fabrication cost; (b) a simple blanket configuration which results in reliability advantages; (c) a very small breeder volume is employed to reduce the tritium inventory and the blanket cost; (d) a high tritium breeding ratio eliminates the need for an outside tritium supply; (e) a low-pressure system decreases the required steel fraction for structural purposes; (f) a low-temperature operation reduces the swelling concerns for beryllium; and (g) the small fractions of structure and breeder materials used in the blanket reduce the decay heat source. The key features and design analyses of this blanket are summarized in this paper.

  5. U. S. ITER shield and blanket design activities

    SciTech Connect (OSTI)

    Baker, C.C.

    1989-03-01T23:59:59.000Z

    This paper summarizes nuclear-related work in support of the U.S. effort for the Internatinoal Thermonuclear Experimental Reactor (ITER) Study. Primary tasks carried out during the past year include design improvements of the inboard shield developed for the TIBER concept, scoping studies of a variety of tritium breeding blanket options, development of necessary design guidelines and evaluation criteria for the blanket options, further safety considerations related to nuclear components, and issues regarding structural materials for an ITER device. The blanket concepts considered are the aqueous/Li salt solution, a water-cooled, solid-breeder blanket, a helium-cooled, solid-breeder blanket, a helium-cooled, solid-breeder blanket, a blanket cooled by helium containing lithium-bearing particulates, and a blanket concept based on breeding tritium from He/sup 3/.

  6. Engineering and manufacturing of ITER first mirror mock-ups

    SciTech Connect (OSTI)

    Joanny, M.; Travere, J. M.; Salasca, S.; Corre, Y. [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Marot, L. [Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland); Thellier, C.; Gallay, G.; Cammarata, C.; Passier, B.; Ferme, J. J. [SESO, 305 Rue Louis Armand CS 30504, 13593 Aix-en-Provence Cedex 3 (France)

    2010-10-15T23:59:59.000Z

    Most of the ITER optical diagnostics aiming at viewing and monitoring plasma facing components will use in-vessel metallic mirrors. These mirrors will be exposed to a severe plasma environment and lead to an important tradeoff on their design and manufacturing. As a consequence, investigations are carried out on diagnostic mirrors toward the development of optimal and reliable solutions. The goals are to assess the manufacturing feasibility of the mirror coatings, evaluate the manufacturing capability and associated performances for the mirrors cooling and polishing, and finally determine the costs and delivery time of the first prototypes with a diameter of 200 and 500 mm. Three kinds of ITER candidate mock-ups are being designed and manufactured: rhodium films on stainless steel substrate, molybdenum on TZM substrate, and silver films on stainless steel substrate. The status of the project is presented in this paper.

  7. Atomic Physics in the Quest for Fusion Energy and ITER

    SciTech Connect (OSTI)

    Charles H. Skinner

    2008-02-27T23:59:59.000Z

    The urgent quest for new energy sources has led developed countries, representing over half of the world population, to collaborate on demonstrating the scientific and technological feasibility of magnetic fusion through the construction and operation of ITER. Data on high-Z ions will be important in this quest. Tungsten plasma facing components have the necessary low erosion rates and low tritium retention but the high radiative efficiency of tungsten ions leads to stringent restrictions on the concentration of tungsten ions in the burning plasma. The influx of tungsten to the burning plasma will need to be diagnosed, understood and stringently controlled. Expanded knowledge of the atomic physics of neutral and ionized tungsten will be important to monitor impurity influxes and derive tungsten concentrations. Also, inert gases such as argon and xenon will be used to dissipate the heat flux flowing to the divertor. This article will summarize the spectroscopic diagnostics planned for ITER and outline areas where additional data is needed.

  8. The neutral beam system for ITER is composed of two Heating and Current Drive (H&CD) injectors and

    E-Print Network [OSTI]

    incorporated into ITER's Product Lifecycle Management (PLM) system Figure 3: Illustration of design progress

  9. Implementation of an iterative matching scheme for the Kapchinskij-Vladimirskij equations in the WARP code

    SciTech Connect (OSTI)

    Chilton, Sven; Chilton, Sven H.

    2008-07-01T23:59:59.000Z

    The WARP code is a robust electrostatic particle-in-cell simulation package used to model charged particle beams with strong space-charge forces. A fundamental operation associated with seeding detailed simulations of a beam transport channel is to generate initial conditions where the beam distribution is matched to the structure of a periodic focusing lattice. This is done by solving for periodic, matched solutions to a coupled set of ODEs called the Kapchinskij-Vladimirskij (KV) envelope equations, which describe the evolution of low-order beam moments subject to applied lattice focusing, space-charge defocusing, and thermal defocusing forces. Recently, an iterative numerical method was developed (Lund, Chilton, and Lee, Efficient computation of matched solutions to the KV envelope equations for periodic focusing lattices, Physical Review Special Topics-Accelerators and Beams 9, 064201 2006) to generate matching conditions in a highly flexible, convergent, and fail-safe manner. This method is extended and implemented in the WARP code as a Python package to vastly ease the setup of detailed simulations. In particular, the Python package accommodates any linear applied lattice focusing functions without skew coupling, and a more general set of beam parameter specifications than its predecessor. Lattice strength iteration tools were added to facilitate the implementation of problems with specific applied focusing strengths.

  10. Breeding channel for the ITER blanket with lithium-lead eutectic Li17Pb83

    SciTech Connect (OSTI)

    Danilov, I.; Sidorov, A.; Strebkov, Y. [ENTEK-RDIPE, Moscow (Russian Federation)] [and others

    1994-12-31T23:59:59.000Z

    The report contains some features of using Li{sub 17}Pb{sub 83} eutectic as breeder for ITER fusion reactor. The use of eutectic in the ITER blanket as breeding material has its own advantages. Results of improvements of lithium-lead blanket channels are described in the report. Design analysis, operation conditions of breeding channels, technique of filling up with eutectic and tritium recovery problems are considered. The eutectic detritization is performed outside and also inside the reactor without removing the eutectic from the blanket. The report contains a survey of investigations of eutectic and channel structure thermal-mechanical behavior, that was the cause of the up to date channel design improvement. The first stage of the thermal and mechanical tests results in change of the channel structure to the sectioning one. The comprehensive tests of the channel models including thermo-mechanical effect of eutectic on the channel structure at the different operating conditions of the channel including the accident ones, the techniques for handling with eutectic etc. to justify the design decisions concerning the breeding eutectic blanket. Suggestions for the further development of the channel design are presented.

  11. Qualification of the Joints for the ITER Central Solenoid

    SciTech Connect (OSTI)

    Martovetsky, N; Berryhill, A; Kenney, S

    2011-09-01T23:59:59.000Z

    The ITER Central Solenoid has 36 interpancake joints, 12 bus joints, and 12 feeder joints in the magnet. The joints are required to have resistance below 4 nOhm at 45 kA at 4.5 K. The US ITER Project Office developed two different types of interpancake joints with some variations in details in order to find a better design, qualify the joints, and establish a fabrication process. We built and tested four samples of the sintered joints and two samples with butt-bonded joints (a total of eight joints). Both designs met the specifications. Results of the joint development, test results, and selection of the baseline design are presented and discussed in the paper. The ITER Central Solenoid (CS) consists of six modules. Each module is composed of six wound hexapancakes and one quadrapancake. The multipancakes are connected electrically and hydraulically by in-line interpancake joints. The joints are located at the outside diameter (OD) of the module. Cable in conduit conductor (CICC) high-current joints are critical elements in the CICC magnets. In addition to low resistivity, the CS joints must fit a space envelope equivalent to the regular conductor cross section and must have low hydraulic impedance and enough structural strength to withstand the hoop and compressive forces during operation, including cycling. This paper is the continuation of the work reported on the intermodule joints.

  12. Progress and present status of ITER cryoline system

    SciTech Connect (OSTI)

    Badgujar, S.; Bonneton, M.; Chalifour, M.; Forgeas, A.; Serio, L. [ITER Organization, Route de Vinon sur Verdon, 13115 St. Paul lez Durance (France); Sarkar, B.; Shah, N. [ITER-India, Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

    2014-01-29T23:59:59.000Z

    The cryoline system at ITER forms a very complex network localized inside the Tokamak building, on a dedicated plant bridge and in cryoplant areas. The cooling power produced in the cryoplant is distributed via these lines with a total length of about 3.7 km and interconnecting all the cold boxes of the cryogenic system as well as the cold boxes of various clients (magnets, cryopumps and thermal shield). Distinct layouts and polygonal geometry, nuclear safety and confinement requirements, difficult installation and in-service inspection/repair demand very high reliability and availability for the cryolines. The finalization of the building-embedded plates for supporting the lines, before the detailed design, has made this project technologically more challenging. The conceptual design phase has been completed and procurement arrangements have been signed with India, responsible for providing the system of cryolines and warm lines to ITER, as in kind contribution. The prototype test for the design and performance validation has been planned on a representative cryoline section. After describing the basic features and general layout of the ITER cryolines, the paper presents key design requirements, conceptual design approach, progress and status of the cryolines project as well as challenges to build such a complex cryoline system.

  13. Water-cooled solid-breeder concept for ITER

    SciTech Connect (OSTI)

    Gohar, Y.; Baker, C.C.; Attaya, H.; Billone, M.; Clemmer, R.C.; Finn, P.A.; Hassanein, A.; Johnson, C.E.; Majumdar, S.; Mattas, R.F.

    1988-08-01T23:59:59.000Z

    A water-cooled solid-breeder blanket concept was developed for ITER. The main function of this blanket is to produce the necessary tritium for the ITER operation. Several design features are incorporated in this blanket concept to increase its attractiveness. It is assumed that the blanket operation at commercial power reactor conditions can be sacrificed to achieve a high tritium breeding ratio with minimum additional research and development, and minimal impact on reactor design and operation. Operating temperature limits are enforced for each material to insure a satisfactory blanket performance. In fact, the design was iterated to maximize the tritium breeding ratio and satisfy these temperature limits. The other design constraint is to permit a large increase in the neutron wall loading without exceeding the temperature limits for the different blanket materials. The blanket concept contains 1.8 cm of Li/sub 2/O and 22.5 cm of beryllium both with a 0.8 density factor. The water coolant is isolated from the breeder material by several zones which reduces the tritium buildup in the water by permeation, reduces the chance for water-breeder interaction, and permits the breeder to operate at high temperature with a low temperature coolant. This improves the safety and environmental aspects of the blanket and eliminates the costly process of the tritium recovery from the water. The key features and design analysis of this blanket are summarized in this paper. 11 refs., 2 figs., 3 tabs.

  14. STUDENT EMPLOYMENT Student Involvement Outcomes

    E-Print Network [OSTI]

    de Lijser, Peter

    STUDENT EMPLOYMENT Student Involvement Outcomes reflective assessment High impact practices. Employment Structure ASI employs approximately 645 staff, interns, and volunteers on average during the fall and spring semesters. In spring 2013, ASI employed: · 42 Interns · 59 Professional Staff Members · 162

  15. Iterative linear solvers in a 2D radiation-hydrodynamics code: Methods and performance

    SciTech Connect (OSTI)

    Baldwin, C.; Brown, P.N.; Falgout, R.; Graziani, F.; Jones, J.

    1999-09-01T23:59:59.000Z

    Computer codes containing both hydrodynamics and radiation play a central role in simulating both astrophysical and inertial confinement fusion (ICF) phenomena. A crucial aspect of these codes is that they require an implicit solution of the radiation diffusion equations. The authors present in this paper the results of a comparison of five different linear solvers on a range of complex radiation and radiation-hydrodynamics problems. The linear solvers used are diagonally scaled conjugate gradient, GMRES with incomplete LU preconditioning, conjugate gradient with incomplete Cholesky preconditioning, multigrid, and multigrid-preconditioned conjugate gradient. These problems involve shock propagation, opacities varying over 5--6 orders of magnitude, tabular equations of state, and dynamic ALE (Arbitrary Lagrangian Eulerian) meshes. They perform a problem size scalability study by comparing linear solver performance over a wide range of problem sizes from 1,000 to 100,000 zones. The fundamental question they address in this paper is: Is it more efficient to invert the matrix in many inexpensive steps (like diagonally scaled conjugate gradient) or in fewer expensive steps (like multigrid)? In addition, what is the answer to this question as a function of problem size and is the answer problem dependent? They find that the diagonally scaled conjugate gradient method performs poorly with the growth of problem size, increasing in both iteration count and overall CPU time with the size of the problem and also increasing for larger time steps. For all problems considered, the multigrid algorithms scale almost perfectly (i.e., the iteration count is approximately independent of problem size and problem time step). For pure radiation flow problems (i.e., no hydrodynamics), they see speedups in CPU time of factors of {approx}15--30 for the largest problems, when comparing the multigrid solvers relative to diagonal scaled conjugate gradient.

  16. Multiscale modeling of solar cells with interface phenomena

    E-Print Network [OSTI]

    Foster, David H; Peszynska, Malgorzata; Schneider, Guenter

    2013-01-01T23:59:59.000Z

    We describe a mathematical model for heterojunctions in semiconductors which can be used, e.g., for modeling higher efficiency solar cells. The continuum model involves well-known drift-diffusion equations posed away from the interface. These are coupled with interface conditions with a nonhomogeneous jump for the potential, and Robin-like interface conditions for carrier transport. The interface conditions arise from approximating the interface region by a lower-dimensional manifold. The data for the interface conditions are calculated by a Density Functional Theory (DFT) model over a few atomic layers comprising the interface region. We propose a domain decomposition method (DDM) approach to decouple the continuum model on subdomains which is implemented in every step of the Gummel iteration. We show results for CIGS/CdS, Si/ZnS, and Si/GaAs heterojunctions.

  17. Investigation of statistical iterative reconstruction for dedicated breast CT

    SciTech Connect (OSTI)

    Makeev, Andrey; Glick, Stephen J. [UMass Medical School, 55 Lake Avenue North, Worcester, Massachusetts 01655 (United States)] [UMass Medical School, 55 Lake Avenue North, Worcester, Massachusetts 01655 (United States)

    2013-08-15T23:59:59.000Z

    Purpose: Dedicated breast CT has great potential for improving the detection and diagnosis of breast cancer. Statistical iterative reconstruction (SIR) in dedicated breast CT is a promising alternative to traditional filtered backprojection (FBP). One of the difficulties in using SIR is the presence of free parameters in the algorithm that control the appearance of the resulting image. These parameters require tuning in order to achieve high quality reconstructions. In this study, the authors investigated the penalized maximum likelihood (PML) method with two commonly used types of roughness penalty functions: hyperbolic potential and anisotropic total variation (TV) norm. Reconstructed images were compared with images obtained using standard FBP. Optimal parameters for PML with the hyperbolic prior are reported for the task of detecting microcalcifications embedded in breast tissue.Methods: Computer simulations were used to acquire projections in a half-cone beam geometry. The modeled setup describes a realistic breast CT benchtop system, with an x-ray spectra produced by a point source and an a-Si, CsI:Tl flat-panel detector. A voxelized anthropomorphic breast phantom with 280 ?m microcalcification spheres embedded in it was used to model attenuation properties of the uncompressed woman's breast in a pendant position. The reconstruction of 3D images was performed using the separable paraboloidal surrogates algorithm with ordered subsets. Task performance was assessed with the ideal observer detectability index to determine optimal PML parameters.Results: The authors' findings suggest that there is a preferred range of values of the roughness penalty weight and the edge preservation threshold in the penalized objective function with the hyperbolic potential, which resulted in low noise images with high contrast microcalcifications preserved. In terms of numerical observer detectability index, the PML method with optimal parameters yielded substantially improved performance (by a factor of greater than 10) compared to FBP. The hyperbolic prior was also observed to be superior to the TV norm. A few of the best-performing parameter pairs for the PML method also demonstrated superior performance for various radiation doses. In fact, using PML with certain parameter values results in better images, acquired using 2 mGy dose, than FBP-reconstructed images acquired using 6 mGy dose.Conclusions: A range of optimal free parameters for the PML algorithm with hyperbolic and TV norm-based potentials is presented for the microcalcification detection task, in dedicated breast CT. The reported values can be used as starting values of the free parameters, when SIR techniques are used for image reconstruction. Significant improvement in image quality can be achieved by using PML with optimal combination of parameters, as compared to FBP. Importantly, these results suggest improved detection of microcalcifications can be obtained by using PML with lower radiation dose to the patient, than using FBP with higher dose.

  18. Self-consistent simulation of plasma scenarios for ITER using a combination of 1.5D transport codes and free-boundary equilibrium codes

    E-Print Network [OSTI]

    Parail, V; Ambrosino, R; Artaud, J-F; Besseghir, K; Cavinato, M; Corrigan, G; Garcia, J; Garzotti, L; Gribov, Y; Imbeaux, F; Koechl, F; Labate, C V; Lister, J; Litaudon, X; Loarte, A; Maget, P; Mattei, M; McDonald, D; Nardon, E; Saibene, G; Sartori, R; Urban, J

    2013-01-01T23:59:59.000Z

    Self-consistent transport simulation of ITER scenarios is a very important tool for the exploration of the operational space and for scenario optimisation. It also provides an assessment of the compatibility of developed scenarios (which include fast transient events) with machine constraints, in particular with the poloidal field (PF) coil system, heating and current drive (H&CD), fuelling and particle and energy exhaust systems. This paper discusses results of predictive modelling of all reference ITER scenarios and variants using two suite of linked transport and equilibrium codes. The first suite consisting of the 1.5D core/2D SOL code JINTRAC [1] and the free boundary equilibrium evolution code CREATE-NL [2,3], was mainly used to simulate the inductive D-T reference Scenario-2 with fusion gain Q=10 and its variants in H, D and He (including ITER scenarios with reduced current and toroidal field). The second suite of codes was used mainly for the modelling of hybrid and steady state ITER scenarios. It...

  19. Development of a Tritium Extruder for ITER Pellet Injection

    SciTech Connect (OSTI)

    M.J. Gouge; P.W. Fisher

    1998-09-01T23:59:59.000Z

    As part of the International Thermonuclear Experimental Reactor (ITER) plasma fueling development program, Oak Ridge National Laboratory (ORNL) has fabricated a pellet injection system to test the mechanical and thermal properties of extruded tritium. Hydrogenic pellets will be used in ITER to sustain the fusion power in the plasma core and may be crucial in reducing first-wall tritium inventories by a process of "isotopic fueling" in which tritium-rich pellets fuel the burning plasma core and deuterium gas fuels the edge. This repeating single-stage pneumatic pellet injector, called the Tritium-Proof-of-Principle Phase II (TPOP-II) Pellet Injector, has a piston-driven mechanical extruder and is designed to extrude and accelerate hydrogenic pellets sized for the ITER device. The TPOP-II program has the following development goals: evaluate the feasibility of extruding tritium and deuterium-tritium (D-T) mixtures for use in future pellet injection systems; determine the mechanical and thermal properties of tritium and D-T extrusions; integrate, test, and evaluate the extruder in a repeating, single-stage light gas gun that is sized for the ITER application (pellet diameter -7 to 8 mm); evaluate options for recycling propellant and extruder exhaust gas; and evaluate operability and reliability of ITER prototypical fueling systems in an environment of significant tritium inventory that requires secondary and room containment systems. In tests with deuterium feed at ORNL, up to 13 pellets per extrusion have been extruded at rates up to 1 Hz and accelerated to speeds of 1.0 to 1.1 km/s, using hydrogen propellant gas at a supply pressure of 65 bar. Initially, deuterium pellets 7.5 mm in diameter and 11 mm in length were produced-the largest cryogenic pellets produced by the fusion program to date. These pellets represent about a 10% density perturbation to ITER. Subsequently, the extruder nozzle was modified to produce pellets that are almost 7.5-mm right circular cylinders. Tritium and D-T pellets have been produced in experiments at the Los Alamos National Laboratory Tritium Systems Test Assembly. About 38 g of tritium have been utilized in the experiment. The tritium was received in eight batches, six from product containers and two from the Isotope Separation System. Two types of runs were made: those in which the material was only extruded and those in which pellets were produced and fired with deuterium propellant. A total of 36 TZ runs and 28 D-T runs have been made. A total of 36 pure tritium runs and 28 D-T mixture runs were made. Extrusion experiments indicate that both T2 and D-T will require higher extrusion forces than D2 by about a factor of two.

  20. ISIS++Reference Guide (Iterative Scalable Implicit Solver in C++) Version 1.1

    SciTech Connect (OSTI)

    Alan B. Williams; Benjamin A. Allan; Kyran D. Mish; Robert L. Clay

    1999-04-01T23:59:59.000Z

    ISIS++ (Iterative Scalable Implicit Solver in C++) Version 1.1 is a portable, object-oriented framework for solving sparse linear systems of equations. It includes a collection of Krylov solution methods and preconditioners, as well as both uni-processor (serial) and multi-processor (scalable) matrix and vector classes. Though it was developed to solve systems of equations originating from large-scale, 3-D, finite element analyses, it has application in many other fields. This document supersedes the ISIS++ V1.0 Reference Guide, defines the V1. 1 interface specification, and includes the necessary instructions for building and running ISIS++ v 1.1 on Unix platforms. The interface is presented in annotated header format, along with background on design and implementation considerations. A finite difference modeling example problem is included to demonstrate the overall setup and use.

  1. PISCES FY11 Research Highlight Tritium accumulation within the ITER vessel is expected to be dominated

    E-Print Network [OSTI]

    PISCES FY11 Research Highlight Tritium accumulation within the ITER vessel is expected vessel. Another possible technique to mitigate tritium accumulation in these codeposited surfaces

  2. US ITER is a strong contributor in plan to enhance international...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    to housing the extensive diagnostic systems that will be installed on the ITER tokamak. (Photo by Elle StarkmanPPPL Office of Communications) PPPL's Russell Feder, left,...

  3. Iterative Krylov solution methods for geophysical electromagnetic simulations on throughput-oriented processing units

    E-Print Network [OSTI]

    Commer, M.

    2012-01-01T23:59:59.000Z

    R. , 1992. Conjugate gradient type methods for linearand bi-conjugate gradient iterative methods to solve complexcase, the conjugate gradient (CG) method of Hestenes and

  4. PPPL and ITER: Lab teams support the world's largest fusion experiment...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    port plugs inside the ITER tokamak. Included in the modular design are stainless steel components called diagnostic first walls that will directly face the plasma. These...

  5. The impact of ELMs on the ITER divertor

    SciTech Connect (OSTI)

    Leonard, A.W.; Osborne, T.H.; Suttrop, W. [General Atomics, San Diego, CA (United States); Hermann, A. [Max Planck Inst. fuer Plasmaphysics, Garching (Germany); Itami, K. [Japan Atomic Energy Research Inst. (Japan); Lingertat, J. [JET Joint Undertaking, Abingdon (United Kingdom); Loarte, A. [Next European Torus, Garching (Germany)

    1998-07-01T23:59:59.000Z

    Edge-Localized-Modes (ELMs) are expected to present a significant transient flux of energy and particles to the ITER divertor. The threshold for ablation of the graphite target will be reached if the ELM transient exceeds Q/t{sup 1/2} {approximately} 45 MJ-m{sup {minus}2}-s{sup {minus}1/2} where Q is the ELM deposition energy density and t is the ELM deposition time. The ablation parameter in ITER can be determined by scaling four factors from present experiments: the ELM energy loss from the core plasma, the fraction of ELM energy deposited on the divertor target, the area of the ELM profile onto the target, and finally the time for the ELM deposition. Review of the ELM energy loss of Type 1 ELM data suggests an ITER ELM energy loss of 2--6% of the stored energy or 25--80 MJ. The fraction of heating power crossing the separatrix due to ELMs is nearly constant (20--40%) resulting in an inverse relationship between ELM amplitude and frequency. Measurements on DIII-D and ASDEX-Upgrade indicate that 50--80% of the ELM energy is deposited on the target. There is currently no evidence for a large fraction of the ELM energy being dissipated through radiation. Profiles of the ELM heat flux are typically 1--2 times the width of steady heat flux between ELMs, with the ELM amplitude usually larger on the inboard target. The ELM deposition time varies from about 0.1 ms in JET to as high as 1.0 ms in ASDEX-Upgrade and DIII-D. The ELM deposition time for ITER will depend upon the level of conductive versus convective transport determined by the ratio of energy to particles released by the ELM. Preliminary analysis suggests that large Type 1 ELMs for low recycling H-mode may exceed the ablation parameter by a factor of 5. Promising regimes with smaller ELMS have been found at other edge operational regimes, including high density with gas puffing, use of rf heating and operation with Type 3 ELMs.

  6. MELCOR ex-vessel LOCA simulations for ITER{sup +}

    SciTech Connect (OSTI)

    Gaeta, M.J.; Merrill, B.J. [Idaho National Engineering Lab., Idaho Falls, ID (United States); Bartels, H.W. [ITER San Diego Joint Work Site, La Jolla, CA (United States)] [and others

    1995-11-01T23:59:59.000Z

    Ex-vessel Loss-of-Coolant-Accident (LOCA) simulations for the International Thermonuclear Experimental Reactor (ITER) were performed using the MELCOR code. The main goals of this work were to estimate the ultimate pressurization of the heat transport system (HTS) vault in order to gauge the potential for stack releases and to estimate the total amount of hydrogen generated during a design basis ex-vessel LOCA. Simulation results indicated that the amount of hydrogen produced in each transient was below the flammability limit for the plasma chamber. In addition, only moderate pressurization of the HTS vault indicated a very small potential for releases through the stack.

  7. U.S. ITER | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItemResearch >Internship Program TheSite Map Site Map Home PageSurvey Forms AllITER

  8. Project Manager Ned Sauthoff Talks About US ITER

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible forPortsmouth/Paducah47,193.70 Hg MercuryProject Final Report:ProjectProjectITER Project

  9. Flow distribution analysis on the cooling tube network of ITER thermal shield

    SciTech Connect (OSTI)

    Nam, Kwanwoo; Chung, Wooho; Noh, Chang Hyun; Kang, Dong Kwon; Kang, Kyoung-O; Ahn, Hee Jae; Lee, Hyeon Gon [ITER Korea, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of)

    2014-01-29T23:59:59.000Z

    Thermal shield (TS) is to be installed between the vacuum vessel or the cryostat and the magnets in ITER tokamak to reduce the thermal radiation load to the magnets operating at 4.2K. The TS is cooled by pressurized helium gas at the inlet temperature of 80K. The cooling tube is welded on the TS panel surface and the composed flow network of the TS cooling tubes is complex. The flow rate in each panel should be matched to the thermal design value for effective radiation shielding. This paper presents one dimensional analysis on the flow distribution of cooling tube network for the ITER TS. The hydraulic cooling tube network is modeled by an electrical analogy. Only the cooling tube on the TS surface and its connecting pipe from the manifold are considered in the analysis model. Considering the frictional factor and the local loss in the cooling tube, the hydraulic resistance is expressed as a linear function with respect to mass flow rate. Sub-circuits in the TS are analyzed separately because each circuit is controlled by its own control valve independently. It is found that flow rates in some panels are insufficient compared with the design values. In order to improve the flow distribution, two kinds of design modifications are proposed. The first one is to connect the tubes of the adjacent panels. This will increase the resistance of the tube on the panel where the flow rate is excessive. The other design suggestion is that an orifice is installed at the exit of tube routing where the flow rate is to be reduced. The analysis for the design suggestions shows that the flow mal-distribution is improved significantly.

  10. Advancing the Physics Basis of Quiescent H-mode through Exploration of ITER Relevant Parameters

    SciTech Connect (OSTI)

    Solomon, W. M. [PPPL; Burrell, K. H. [General Atomics; Fenstermacher, M. E. [LLNL; Garofalo, A. M. [General Atomics; Grierson, B. A. [PPPL; Loarte, A. [ITER; McKee, G. R. [U of Wisc, Madison; Nazikian, R. [PPPL; Snyder, B. P. [General Atomics

    2014-09-01T23:59:59.000Z

    Recent experiments on DIII-D have overcome a long-standing limitation in accessing quiescent H-mode (QH-mode), a high confinement state of the plasma that does not exhibit the explosive instabilities associated with edge localized modes (ELMs). In the past, QH-mode was associated with low density operation, but has now been extended to high normalized densities compatible with operation envisioned for ITER. Through the use of strong shaping, QH-mode plasmas have been maintained at high densities, both absolute (?e ? 7 × 1019 m—3) and normalized Greenwald fraction (?e/?G > 0:7) . In these plasmas, the pedestal can evolve to very high pressures and current as the density is increased. Calculations of the pedestal height and width from the EPED model are quantitatively consistent with the experimental observed evolution with density. The comparison of the dependence of the maximum density threshold for QH-mode with plasma shape help validate the underlying theoretical peeling-ballooning models describing ELM stability. High density QH-mode operation with strong shaping has allowed stable access to a previously predicted regime of very high pedestal dubbed \\Super H-mode". In general, QH-mode is found to achieve ELM-stable operation while maintaining adequate impurity exhaust, due to the enhanced impurity transport from an edge harmonic oscillation, thought to be a saturated kink- peeling mode driven by rotation shear. In addition, the impurity confinement time is not affected by rotation, even though the energy confinement time and measured E ? B shear is observed to increase at low toroidal rotation. Together with demonstrations of high beta, high confinement and low q95 for many energy confinement times, these results suggest QH-mode as a potentially attractive operating scenario for ITER's Q=10 mission.

  11. Iterative prediction of chaotic time series using a recurrent neural network

    SciTech Connect (OSTI)

    Essawy, M.A.; Bodruzzaman, M. [Tennessee State Univ., Nashville, TN (United States). Dept. of Electrical and Computer Engineering; Shamsi, A.; Noel, S. [USDOE Morgantown Energy Technology Center, WV (United States)

    1996-12-31T23:59:59.000Z

    Chaotic systems are known for their unpredictability due to their sensitive dependence on initial conditions. When only time series measurements from such systems are available, neural network based models are preferred due to their simplicity, availability, and robustness. However, the type of neutral network used should be capable of modeling the highly non-linear behavior and the multi-attractor nature of such systems. In this paper the authors use a special type of recurrent neural network called the ``Dynamic System Imitator (DSI)``, that has been proven to be capable of modeling very complex dynamic behaviors. The DSI is a fully recurrent neural network that is specially designed to model a wide variety of dynamic systems. The prediction method presented in this paper is based upon predicting one step ahead in the time series, and using that predicted value to iteratively predict the following steps. This method was applied to chaotic time series generated from the logistic, Henon, and the cubic equations, in addition to experimental pressure drop time series measured from a Fluidized Bed Reactor (FBR), which is known to exhibit chaotic behavior. The time behavior and state space attractor of the actual and network synthetic chaotic time series were analyzed and compared. The correlation dimension and the Kolmogorov entropy for both the original and network synthetic data were computed. They were found to resemble each other, confirming the success of the DSI based chaotic system modeling.

  12. Solid breeder blanket option for the ITER conceptual design

    SciTech Connect (OSTI)

    Gohar, Y.; Attaya, H.; Billone, M.C.; Finn, P.; Majumdar, S.; Turner, L.R.; Baker, C.C.; Nelson, B.E.; Raffray, R. (Argonne National Lab., IL (USA); Oak Ridge National Lab., TN (USA); California Univ., Los Angeles, CA (USA))

    1989-10-01T23:59:59.000Z

    A solid-breeder water-cooled blanket option was developed for ITER based on a multilayer configuration. The blanket uses beryllium for neutron multiplication and lithium oxide for tritium breeding. The material forms are sintered products for both material with 0.8 density factor. The lithium-6 enrichment is 90%. This blanket has the capability to accommodate a factor of two change in the neutron wall loading without violating the different design guidelines. The design philosophy adopted for the blanket is to produce the necessary tritium required for the ITER operation and to operate at power reactor conditions as much as possible. At the same time, the reliability and the safety aspects of the blanket are enhanced by the use of a low-pressure coolant and the separation of the tritium purge lines from the coolant system. The blanket modules are made by hot vacuum forming and diffusion bonding a double wall structure with integral cooling channels. The different aspects of the blanket design including tritium breeding, nuclear heat deposition, activation analyses, thermal-hydraulics, tritium inventory, structural analyses, and water coolant conditions are summarized in this paper. 12 refs., 2 figs., 1 tab.

  13. Assessment Of An Oblique ECE Diagnostic For ITER

    SciTech Connect (OSTI)

    Gary Taylor and Robert W. Harvey

    2009-07-15T23:59:59.000Z

    A systematic disagreement between the electron temperature measured by electron cyclotron emission (TECE) and laser Thomson scattering (TTS), that increases with TECE, is observed in JET and TFTR plasmas, such that TECE ~ 1.2 TTS when TECE ~ 10 keV. The disagreement is consistent with a non-Maxwellian distortion in the bulk electron momentum distribution. ITER is projected to operate with Te(0) ~ 20-40 keV so the disagreement between TECE and TTS could be > 50%, with significant physics implications. The GENRAY ray tracing code predicts that a two-view ECE system, with perpendicular and moderately oblique viewing antennas, would be sufficient to reconstruct a two-temperature bulk distribution. If the electron momentum distribution remains Maxwellian the moderately oblique view could still be used to measure Te(R). A viewing dump will not be required for the oblique view and plasma refraction will be minimal. The oblique view has a similar radial resolution to the perpendicular view, but with some reduction in radial coverage. Oblique viewing angles of up to 20o can be implemented without a major revision to the front end of the existing ITER ECE diagnostic design.

  14. Chevron beam dump for ITER edge Thomson scattering system

    SciTech Connect (OSTI)

    Yatsuka, E.; Hatae, T.; Bassan, M.; Itami, K. [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan)] [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan); Vayakis, G. [ITER Organization, 13115 St Paul Lez Durance Cedex (France)] [ITER Organization, 13115 St Paul Lez Durance Cedex (France)

    2013-10-15T23:59:59.000Z

    This paper contains the design of the beam dump for the ITER edge Thomson scattering system and mainly concerns its lifetime under the harsh thermal and electromagnetic loads as well as tight space allocation. The lifetime was estimated from the multi-pulse laser-induced damage threshold. In order to extend its lifetime, the structure of the beam dump was optimized. A number of bent sheets aligned parallel in the beam dump form a shape called a chevron which enables it to avoid the concentration of the incident laser pulse energy. The chevron beam dump is expected to withstand thermal loads due to nuclear heating, radiation from the plasma, and numerous incident laser pulses throughout the entire ITER project with a reasonable margin for the peak factor of the beam profile. Structural analysis was also carried out in case of electromagnetic loads during a disruption. Moreover, detailed issues for more accurate assessments of the beam dump's lifetime are clarified. Variation of the bi-directional reflection distribution function (BRDF) due to erosion by or contamination of neutral particles derived from the plasma is one of the most critical issues that needs to be resolved. In this paper, the BRDF was assumed, and the total amount of stray light and the absorbed laser energy profile on the beam dump were evaluated.

  15. Iterative image-domain decomposition for dual-energy CT

    SciTech Connect (OSTI)

    Niu, Tianye; Dong, Xue; Petrongolo, Michael; Zhu, Lei, E-mail: leizhu@gatech.edu [Nuclear and Radiological Engineering and Medical Physics Programs, The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)] [Nuclear and Radiological Engineering and Medical Physics Programs, The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)

    2014-04-15T23:59:59.000Z

    Purpose: Dual energy CT (DECT) imaging plays an important role in advanced imaging applications due to its capability of material decomposition. Direct decomposition via matrix inversion suffers from significant degradation of image signal-to-noise ratios, which reduces clinical values of DECT. Existing denoising algorithms achieve suboptimal performance since they suppress image noise either before or after the decomposition and do not fully explore the noise statistical properties of the decomposition process. In this work, the authors propose an iterative image-domain decomposition method for noise suppression in DECT, using the full variance-covariance matrix of the decomposed images. Methods: The proposed algorithm is formulated in the form of least-square estimation with smoothness regularization. Based on the design principles of a best linear unbiased estimator, the authors include the inverse of the estimated variance-covariance matrix of the decomposed images as the penalty weight in the least-square term. The regularization term enforces the image smoothness by calculating the square sum of neighboring pixel value differences. To retain the boundary sharpness of the decomposed images, the authors detect the edges in the CT images before decomposition. These edge pixels have small weights in the calculation of the regularization term. Distinct from the existing denoising algorithms applied on the images before or after decomposition, the method has an iterative process for noise suppression, with decomposition performed in each iteration. The authors implement the proposed algorithm using a standard conjugate gradient algorithm. The method performance is evaluated using an evaluation phantom (Catphan©600) and an anthropomorphic head phantom. The results are compared with those generated using direct matrix inversion with no noise suppression, a denoising method applied on the decomposed images, and an existing algorithm with similar formulation as the proposed method but with an edge-preserving regularization term. Results: On the Catphan phantom, the method maintains the same spatial resolution on the decomposed images as that of the CT images before decomposition (8 pairs/cm) while significantly reducing their noise standard deviation. Compared to that obtained by the direct matrix inversion, the noise standard deviation in the images decomposed by the proposed algorithm is reduced by over 98%. Without considering the noise correlation properties in the formulation, the denoising scheme degrades the spatial resolution to 6 pairs/cm for the same level of noise suppression. Compared to the edge-preserving algorithm, the method achieves better low-contrast detectability. A quantitative study is performed on the contrast-rod slice of Catphan phantom. The proposed method achieves lower electron density measurement error as compared to that by the direct matrix inversion, and significantly reduces the error variation by over 97%. On the head phantom, the method reduces the noise standard deviation of decomposed images by over 97% without blurring the sinus structures. Conclusions: The authors propose an iterative image-domain decomposition method for DECT. The method combines noise suppression and material decomposition into an iterative process and achieves both goals simultaneously. By exploring the full variance-covariance properties of the decomposed images and utilizing the edge predetection, the proposed algorithm shows superior performance on noise suppression with high image spatial resolution and low-contrast detectability.

  16. Thermo-mechanical analysis of ITER first mirrors and its use for the ITER equatorial visible/infrared wide angle viewing system optical design

    SciTech Connect (OSTI)

    Joanny, M.; Salasca, S.; Dapena, M.; Cantone, B.; Travere, J. M. [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Thellier, C.; Ferme, J. J. [THALES SESO, 13593 Aix-en-Provence Cedex 3 (France); Marot, L. [Department of Physics, University of Basel, 4056 Basel (Switzerland); Buravand, O. [Institut d'Optique Graduate School, 91127 Palaiseau (France); Perrollaz, G. [AMETRA, 13770 Venelles (France); Zeile, C. [INR, KIT, D-76344 Eggenstein-Leopoldshafen (Germany)

    2012-10-15T23:59:59.000Z

    ITER first mirrors (FMs), as the first components of most ITER optical diagnostics, will be exposed to high plasma radiation flux and neutron load. To reduce the FMs heating and optical surface deformation induced during ITER operation, the use of relevant materials and cooling system are foreseen. The calculations led on different materials and FMs designs and geometries (100 mm and 200 mm) show that the use of CuCrZr and TZM, and a complex integrated cooling system can limit efficiently the FMs heating and reduce their optical surface deformation under plasma radiation flux and neutron load. These investigations were used to evaluate, for the ITER equatorial port visible/infrared wide angle viewing system, the impact of the FMs properties change during operation on the instrument main optical performances. The results obtained are presented and discussed.

  17. Total-system performance assessment for Yucca Mountain -- SNL second iteration (TSPA-1993); Executive summary

    SciTech Connect (OSTI)

    Wilson, M.L.; Barnard, R.W. [Sandia National Labs., Albuquerque, NM (United States); Gauthier, J.H. [Sandia National Labs., Albuquerque, NM (United States)]|[Spectra Research, Inc. (United States)] [and others

    1994-04-01T23:59:59.000Z

    Sandia National Laboratories has completed the second iteration of the periodic total-system performance assessments (TSPA-93) for the Yucca Mountain Site Characterization Project (YMP). Scenarios describing expected conditions (aqueous and gaseous transport of contaminants) and low-probability events (human-intrusion drilling and volcanic intrusion) are modeled. The hydrologic processes modeled include estimates of the perturbations to ambient conditions caused by heating of the repository resulting from radioactive decay of the waste. TSPA-93 incorporates significant new detailed process modeling, including two- and three-dimensional modeling of thermal effects, groundwater flow in the saturated-zone aquifers, and gas flow in the unsaturated zone. Probabilistic analyses are performed for aqueous and gaseous flow and transport, human intrusion, and basaltic magmatic activity. Results of the calculations lead to a number of recommendations concerning studies related to site characterization. Primary among these are the recommendations to obtain better information on percolation flux at Yucca Mountain, on the presence or absence of flowing fractures, and on physical and chemical processes influencing gaseous flow. Near-field thermal and chemical processes, and waste-container degradation are also areas where additional investigations may reduce important uncertainties. Recommendations for repository and waste-package design studies are: (1) to evaluate the performance implications of large-size containers, and (2) to investigate in more detail the implications of high repository thermal power output on the adjacent host rock and on the spent fuel.

  18. Presented by Y.Shimomura ITER Joint Central Team and Home Teams

    E-Print Network [OSTI]

    of reliability of the operation Full commissioning of the ITER systemin a non-nuclear environment DevelopmentPresented by Y.Shimomura ITER Joint Central Team and Home Teams Oct. 5, 2000 Sorrento, Italy #12 Elevation Layout #12;Phased Operations Hydrogen Phase Confirmation of the machine performance and increase

  19. A Generalized Diffusion Based Inter-Iteration Nonlinear Bilateral Filtering Scheme for PET

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    A Generalized Diffusion Based Inter-Iteration Nonlinear Bilateral Filtering Scheme for PET Image inter-iteration filtering scheme based diffusion MAP estimate for PET image reconstruction is proposed,version1 #12;1. Introduction Positron emission tomography (PET) is one of the most important imaging tools

  20. PARSMI, a parallel revised simplex algorithm incorporating minor iterations and Devex pricing

    E-Print Network [OSTI]

    Hall, Julian

    PARSMI, a parallel revised simplex algorithm incorporating minor iterations and Devex pricing J, a parallel revised simplex algorithm incorporating minor iterations and Devex pricing J. A. J. Hall and K. I linear programming problems using the re- vised simplex method, two common variants are the incorporation

  1. An iterative process for international negociations on acid rain in Northern Europe

    E-Print Network [OSTI]

    Toint, Philippe

    An iterative process for international negociations on acid rain in Northern Europe using a general 138.48.4.14) #12; An iterative process for international negotiations on acid rain in Northern Europe transboundary pollution problem related to acid rain in Northern Europe. This simulation shows the need

  2. ISFNT-11, Barcelona, Spain, September 16-20, 2013 2013, ITER Organization

    E-Print Network [OSTI]

    Raffray, A. René

    , Fabrication and Testing of the ITER First Wall and Shielding Blanket Presented by A. René Raffray Blanket Domestic Agency; 7SNL , US ITER Domestic Agency; 11th International Symposium on Fusion Nuclear Technology and neutron loads in the vacuum vessel and ex-vessel components · Provide a plasma-facing surface which

  3. Brussels, 1 April 2006 ITER Project on Track Top Management Team

    E-Print Network [OSTI]

    IP/06/418 Brussels, 1 April 2006 ITER Project on Track ­ Top Management Team Identified Union, India, Japan, Korea, China, Russia and USA), identified the top management team that will manage-General in November 2005, the top management team of the prospective ITER Organization is now complete. The Tokyo

  4. S12.9Constrained Iterative Speech Enhance with Application to

    E-Print Network [OSTI]

    Texas at Dallas, University of

    S12.9Constrained Iterative Speech Enhance with Application to Automatic Speech Recognition John H Atlanta, GA 30332 set of iterative speech enhancement techniques employing spec- ral constraints. FinalIy, the enhancement algorithms are evaluated to determine their ability as preproces- and speech

  5. EXPERIMENTALSTUDY OF THE EFFECTIVETHERMAL CONDUCTIVITYOFA PACKED BED AS A TEMPERATURECONTROL MECHANISMFOR ITER CERAMICBREEDERBLANKETDESIGNS *

    E-Print Network [OSTI]

    Raffray, A. René

    Angeles, CA 90066 Introduction For an ITER ceramic breeding blanket, the breeder temperature must be kept the coolant and solid breeder to allow their operating temperatures to be optimized for ITER.[11 This thermal%) is desired to increase the tritium production in the blanket. The proposed concept also provides operational

  6. Fusion Engineering and Design 81 (2006) 433441 An overview of US ITER test blanket module program

    E-Print Network [OSTI]

    Abdou, Mohamed

    2006-01-01T23:59:59.000Z

    blankets: (1) a helium-cooled solid breeder concept with ferritic steel structure and Be neutron multiplierLi liquid breeder blanket concepts in ITER are identified. © 2005 Elsevier B.V. All rights reserved. Keywords: ITER test blanket module program; Helium-cooled solid breeder blanket; Dual-coolant lead

  7. Fusion Engineering and Design 46 (1999) 177183 ITER reference breeding blanket design

    E-Print Network [OSTI]

    Raffray, A. René

    1999-01-01T23:59:59.000Z

    breeding blanket with a lithium ceramic as breeder material and beryllium as neutron multiplierFusion Engineering and Design 46 (1999) 177­183 ITER reference breeding blanket design M. Ferrari a The ITER reference breeding blanket design is water-cooled and is characterised by the use of the neutronic

  8. CONCURRENT ENGINEERING: Research and Applications Overcoming the 90% Syndrome: Iteration Management

    E-Print Network [OSTI]

    Ford, David N.

    CONCURRENT ENGINEERING: Research and Applications Overcoming the 90% Syndrome: Iteration Management in Concurrent Development Projects David N. Ford1,* and John D. Sterman2 1 Department of Civil Engineering to unanticipated problems and perturbations. Key Words: concurrent development, concurrent engineering, iteration

  9. The European Joint Undertaking for ITER and the Development of Fusion Energy

    E-Print Network [OSTI]

    1 The European Joint Undertaking for ITER and the Development of Fusion Energy (Fusion for Energy Agreement · Last meeting of negotiators took place in Jeju, China in November 2005 · Meeting of legal experts in Barcelona last week resolved most remaining issues #12;3 Tentative ITER Timetable · Political

  10. Looking on bright side of losing ITER Risa Kato and Tetsuro Yamada / Yomiuri Shimbun Staff Writers

    E-Print Network [OSTI]

    to have a remote-controlled ITER experiment unit, and one for the development of super heat candidate to have a remote-control facility is of especially high significance, according to experts. The remote-control facility is envisaged as playing a key role in the ITER project, as it will be able

  11. Annual Report of the EURATOM/CCFE Fusion Programme 2010/11 8 ITER Systems

    E-Print Network [OSTI]

    to the ITER heating, diagnostic and remote handling systems in particular. Fusion for Energy (F4E its substantial role in five key ITER systems: · Ion Cyclotron Resonance Heating (ICRH) system) content, the ion temperature and flow; · Remote handling system, in particular the design for the Neutral

  12. Annual Report of the EURATOM/CCFE Fusion Programme 2013 8 ITER SYSTEMS

    E-Print Network [OSTI]

    and undertake leading or major roles in the design and R&D of ITER specialist systems (Plasma Heating, Diagnostics and Remote Handling etc.). Seek to play other design roles in R&D of ITER specialist systems Resonance Heating (ICRH) system. Neutral Beam Injection heating system. Core LIDAR Thompson scattering

  13. Annual Report of the EURATOM/CCFE Fusion Programme 2012/13 8 ITER SYSTEMS

    E-Print Network [OSTI]

    Heating, Diagnostics and Remote Handling etc). · Seek to play other design roles in R&D of ITER specialist in the following key ITER systems: · Ion Cyclotron Resonance Heating (ICRH) system. · Neutral Beam Injection heating system. · Core LIDAR Thompson scattering to measure the electron temperature and density profiles

  14. Iterative methods for neutron transport eigenvalue Fynn Scheben and Ivan G. Graham

    E-Print Network [OSTI]

    Graham, Ivan

    iterative methods for computing criticality in nuclear reactors. In general this requires the solution words. neutron transport, criticality, generalised eigenvalue problem, symmetry, inexact inverse iteration. AMS subject classifications. 45C05, 65F15, 65N25, 65R20, 65Z05, 82D75 1. Reactor criticality

  15. Visions for data management and remote collaboration for ITER M. Greenwald1

    E-Print Network [OSTI]

    Greenwald, Martin

    Visions for data management and remote collaboration for ITER M. Greenwald1 D. Schissel2 J. R Introduction This paper outlines a vision for data management and remote collaboration systems for ITER scales, leading to requirements for efficient browsing of very long data records and the ability

  16. Fourier-Based Forward and Back-Projectors for Iterative Image Reconstruction

    E-Print Network [OSTI]

    Fessler, Jeffrey A.

    Fourier-Based Forward and Back-Projectors for Iterative Image Reconstruction Samuel Matej, Jeffrey. Fourier-Based Projectors B. Non-Uniform Fast Fourier Transform C. Fourier-Based Iterative Reconstruction D. Fourier-based forward and back-projection methods have the potential to considerably reduce

  17. Dual-dictionary learning-based iterative image reconstruction for spectral computed tomography application

    E-Print Network [OSTI]

    Wang, Ge

    Dual-dictionary learning-based iterative image reconstruction for spectral computed tomography-based iterative image reconstruction for spectral computed tomography application Bo Zhao1 , Huanjun Ding1 , Yang discriminating photon-counting detectors, such as cadmium­zinc­telluride (CZT), in spectral computed tomography

  18. First ITER Council convened in Cadarache Historic step in the quest for clean Energy

    E-Print Network [OSTI]

    First ITER Council convened in Cadarache Historic step in the quest for clean Energy Cadarache, 28 of age in a world in desperate need of clean, abundant, and carbon dioxide-free energy." Setting a new Energy Agency (IAEA), said: "Let me congratulate all who have contributed to the achievements of the ITER

  19. An Optical Programmable Network Architecture Supporting Iterative Multicast for Data-intensive Applications

    E-Print Network [OSTI]

    Ng, T. S. Eugene

    An Optical Programmable Network Architecture Supporting Iterative Multicast for Data. Bergman1 1 Department of Electrical Engineering, Columbia University, 500 West 120th Street, New York, New.edu Abstract--We present an optical programmable network architecture to enable agile and efficient iterative

  20. A E Costley ITER Diagnostics, 21st IAEA of 5 slides

    E-Print Network [OSTI]

    shielding, Tritium containment, vacuum integrity, RH compatibility. #12;A E Costley ITER Diagnostics, 21st distinct measurement systems in total. #12;A E Costley ITER Diagnostics, 21st IAEA 9 of 5 slides HANDLING, Germany THE DESIGN AND IMPLEMENTATIONTHE DESIGN AND IMPLEMENTATION OF DIAGNOSTIC SYSTEMS ON ITEROF

  1. A three-dimensional adaptive method based on the iterative grid redistribution

    E-Print Network [OSTI]

    Wang, Desheng

    grid equation systems and an efficient method for inverting a map by computing isoA three-dimensional adaptive method based on the iterative grid redistribution Desheng Wang on iterative grid redistribution technique introduced in [J. Comput. Phys. 159 (2000) 246]. The key step

  2. Current control in ITER steady state plasmas with neutral beam steering R. V. Budnya

    E-Print Network [OSTI]

    Budny, Robert

    . The heating and current drive systems for ITER plasmas are being designed. The primary systems being for ITER steady state plasmas are specified. Current drive by negative ion neutral beam injection, lower-hybrid as the ratio of the DT fusion and the external heating powers PDT/Pext 5 for durations of up to 3000 s

  3. Nuclear systems and testing programs for ITER. Progress report for FY 1998

    SciTech Connect (OSTI)

    NONE

    1998-12-31T23:59:59.000Z

    The effort during this performance period focused on a number of TBWG activities (including test module design and analysis) that were identified and agreed upon (in the presence of the ITER Director and Deputy Director) at TBWG-4. These include: (a) DEMO test module design and performance analysis under pulsed operation; (b) Test program operation plan; (c) Test port design and analysis; (d) Decay heat calculations and safety analysis; (e) Further discussion among the parties to define collaboratory on R and D for the test program as well as possible collaboration on the construction and operation of test articles; (f) Remote handling and ancillary equipment; (g) Criteria for qualifying a blanket module or submodule for actual insertion and testing in ITER; (h) Definition of test module instrumentation and verification of capability to perform in the ITER fusion environment (magnetic field, radiation, heating, etc.); and (i) Analysis to show that the results to be obtained from the test modules as designed can be extrapolated to DEMO and reactor conditions (e.g., higher wall loads and the need to demonstrate tritium self-sufficiency). The main achievements during this performance period include: (1) updating and finalizing the US DDDs for the ITER Blanket Program to form part of the ITER Final Design Report (FDR). Specific revisions were in response to the minimal lithium volume test blanket design requirements and safety impact and (2) evaluating the feasibility of the US test program, including instrumentation and the benefits of the ITER test program. Details of this assessment, including solid breeder and liquid breeder blanket test plans, are documented in UCLA-IFNT-13 (attached). In addition, dose mapping calculations were performed for the ITER Building, including equipment and layout of coolant pipes/heat exchangers. A report on ITER Building dose calculations was sent to UD ITER management and to the Garching Task Coordinator in April, 1998. The report entitled Three-Dimensional Calculations of ITER Building Dose Rate Profiles and Assessment of Accessibility Inside the Building During Operation and After Shutdown of ITER can be located through ITER Reference Number of ITER Task S 62 TD 12, ID No: D325 ITER/US/98/S62TD12-D325 UCLA-FNT-100 UCLA-ENG-98-190.

  4. Safety Analysis of the US Dual Coolant Liquid Lead-Lithium ITER Test Blanket Module

    SciTech Connect (OSTI)

    Merrill, Brad; Reyes, Susana; Sawan, Mohamed; Wong, Clement

    2006-07-01T23:59:59.000Z

    The US is proposing a prototype of a dual coolant liquid lead-lithium (DCLL) DEMO blanket concept for testing in the International Thermonuclear Experimental Reactor (ITER) as an ITER Test Blanket Module (TBM). Because safety considerations are an integral part of the design process to ensure that this TBM does not adversely impact the safety of ITER, a safety assessment has been conducted for this TBM and its ancillary systems as requested by the ITER project. Four events were selected by the ITER International Team (IT) to address specific reactor safety concerns, such as VV pressurization, confinement building pressure build-up, TBM decay heat removal capability, tritium and activation products release from the TBM system, and hydrogen and heat production from chemical reactions. This paper summarizes the results of this safety assessment conducted with the MELCOR computer code.

  5. ITERATIVE REPAIR PLANNING FOR SPACECRAFT OPERATIONS USING THE ASPEN SYSTEM Gregg Rabideau, Russell Knight, Steve Chien, Alex Fukunaga, Anita Govindjee

    E-Print Network [OSTI]

    Schaffer, Steven

    ITERATIVE REPAIR PLANNING FOR SPACECRAFT OPERATIONS USING THE ASPEN SYSTEM Gregg Rabideau, Russell and Planning Environment (ASPEN). ASPEN encodes complex spacecraft knowledge of operability constraints, flight generation of low level spacecraft sequences. Using a technique called iterative repair, ASPEN classifies

  6. Analysis of Rotating Collectors from the Private Region of JET with Carbon Wall and Metallic ITER-Like Wall

    E-Print Network [OSTI]

    Analysis of Rotating Collectors from the Private Region of JET with Carbon Wall and Metallic ITER-Like Wall

  7. Coupling between JET Pedestal ne-Te and Outer Target Plate Recycling: Consequences for JET ITER-Like-Wall Operation

    E-Print Network [OSTI]

    Coupling between JET Pedestal ne-Te and Outer Target Plate Recycling: Consequences for JET ITER-Like-Wall Operation

  8. Simulation of MGI Efficiency for Plasma Energy Conversion into Ar Radiation in JET and Implications for ITER

    E-Print Network [OSTI]

    Simulation of MGI Efficiency for Plasma Energy Conversion into Ar Radiation in JET and Implications for ITER

  9. Evolution of Plasma Parameters in the Termination Phase of High Confinement H-modes at JET and Implications for ITER

    E-Print Network [OSTI]

    Evolution of Plasma Parameters in the Termination Phase of High Confinement H-modes at JET and Implications for ITER

  10. Reconstruction of Distribution Functions of Fast Ions and Runaway Electrons in ITER Plasmas Using Gamma-Ray Spectrometry

    E-Print Network [OSTI]

    Reconstruction of Distribution Functions of Fast Ions and Runaway Electrons in ITER Plasmas Using Gamma-Ray Spectrometry

  11. High-Energy Fuel Ion Diagnostics on ITER Derived from Neutron Emission Spectroscopy Measurements on JET DT Plasmas

    E-Print Network [OSTI]

    High-Energy Fuel Ion Diagnostics on ITER Derived from Neutron Emission Spectroscopy Measurements on JET DT Plasmas

  12. DESIGN OF THE ITER IN-VESSEL COILS

    SciTech Connect (OSTI)

    Neumeyer, C; Bryant, L; Chrzanowski, J; Feder, R; Gomez, M; Heitzenroeder, P; Kalish, M; Lipski, A; Mardenfeld, M; Simmons, R; Titus, P; Zatz, I; Daly, E; Martin, A; Nakahira, M; Pillsbury, R; Feng, J; Bohm, T; Sawan, M; Stone, H; Griffiths, I

    2010-11-27T23:59:59.000Z

    The ITER project is considering the inclusion of two sets of in-vessel coils, one to mitigate the effect of Edge Localized Modes (ELMs) and another to provide vertical stabilization (VS). The in-vessel location (behind the blanket shield modules, mounted to the vacuum vessel inner wall) presents special challenges in terms of nuclear radiation (~3000 MGy) and temperature (100oC vessel during operations, 200oC during bakeout). Mineral insulated conductors are well suited to this environment but are not commercially available in the large cross section required. An R&D program is underway to demonstrate the production of mineral insulated (MgO or Spinel) hollow copper conductor with stainless steel jacketing needed for these coils. A preliminary design based on this conductor technology has been developed and is presented herein.

  13. Status of ITER neutral beam cell remote handling system

    E-Print Network [OSTI]

    Sykes, N; Choi, C-H; Crofts, O; Crowe, R; Damiani, C; Delavalle, S; Meredith, L; Mindham, T; Raimbach, J; Tesini, A; Van Uffelen, M

    2013-01-01T23:59:59.000Z

    The ITER neutral beam cell will contain up to three heating neutral beams and one diagnostic neutral beam, and four upper ports. Though manual maintenance work is envisaged within the cell, when containment is breached, or the radiological protection is removed the maintenance must be conducted remotely. This maintenance constitutes the removal and replacement of line replaceable units, and their transport to and from a cask docked to the cell. A design of the remote handling system has been prepared to concept level which this paper describes including the development of a beam line transporter, beam source remote handling equipment, upper port remote handling equipment and equipment for the maintenance of the neutral shield. This equipment has been developed complete the planned maintenance tasks for the components of the neutral beam cell and to have inherent flexibility to enable as yet unforeseen tasks and recovery operations to be performed.

  14. Iterative methods for dose reduction and image enhancement in tomography

    DOE Patents [OSTI]

    Miao, Jianwei; Fahimian, Benjamin Pooya

    2012-09-18T23:59:59.000Z

    A system and method for creating a three dimensional cross sectional image of an object by the reconstruction of its projections that have been iteratively refined through modification in object space and Fourier space is disclosed. The invention provides systems and methods for use with any tomographic imaging system that reconstructs an object from its projections. In one embodiment, the invention presents a method to eliminate interpolations present in conventional tomography. The method has been experimentally shown to provide higher resolution and improved image quality parameters over existing approaches. A primary benefit of the method is radiation dose reduction since the invention can produce an image of a desired quality with a fewer number projections than seen with conventional methods.

  15. Development of the bus joint for the ITER Central Solenoid

    SciTech Connect (OSTI)

    Martovetsky, Nicolai N [ORNL] [ORNL; Irick, David Kim [ORNL] [ORNL; Kenney, Steven J [ORNL] [ORNL

    2013-01-01T23:59:59.000Z

    The terminations of the Central Solenoid (CS) modules are connected to the bus extensions by joints located outside the CS in the gap between the CS and Torodial Field (TF) assemblies. These joints have very strict space limitations. Low resistance is a common requirement for all ITER joints. In addition, the CS bus joints will experience and must be designed to withstand significant variation in the magnetic field of several tenths of a Tesla per second during initiation of plasma. The joint resistance is specified to be less than 4 nOhm. The joints also have to be soldered in the field and designed with the possibility to be installed and dismantled in order to allow cold testing in the cold test facility. We have developed coaxial joints that meet these requirements and have demonstrated the feasibility to fabricate and assemble them in the vertical configuration. We introduced a coupling cylinder with superconducting strands soldered to the surface of the cable that can be installed in the ITER assembly hall and at the Cold Test Facility. This cylinder serves as a transition area between the CS module and the bus extension. We made two racetrack samples and tested four bus joints in our Joint Test Apparatus. Resistance of the bus joints was measured by a decay method and by a microvoltmeter; the value of the current was measured by the Hall probes. This measurement method was verified in the previous tests. The resistance of the joints varied insignificantly from 1.5 to 2 nOhm. One of the challenges associated with a soldered joint is the inability to use corrosive chemicals that are difficult to clean. This paper describes our development work on cable preparation, chrome removal, compaction, soldering, and final assembly and presents the test results.

  16. Iterative reconstruction using a Monte Carlo based system transfer matrix for dedicated breast positron emission tomography

    SciTech Connect (OSTI)

    Saha, Krishnendu [Ohio Medical Physics Consulting, Dublin, Ohio 43017 (United States); Straus, Kenneth J.; Glick, Stephen J. [Department of Radiology, University of Massachusetts Medical School, Worcester, Massachusetts 01655 (United States); Chen, Yu. [Department of Radiation Oncology, Columbia University, New York, New York 10032 (United States)

    2014-08-28T23:59:59.000Z

    To maximize sensitivity, it is desirable that ring Positron Emission Tomography (PET) systems dedicated for imaging the breast have a small bore. Unfortunately, due to parallax error this causes substantial degradation in spatial resolution for objects near the periphery of the breast. In this work, a framework for computing and incorporating an accurate system matrix into iterative reconstruction is presented in an effort to reduce spatial resolution degradation towards the periphery of the breast. The GATE Monte Carlo Simulation software was utilized to accurately model the system matrix for a breast PET system. A strategy for increasing the count statistics in the system matrix computation and for reducing the system element storage space was used by calculating only a subset of matrix elements and then estimating the rest of the elements by using the geometric symmetry of the cylindrical scanner. To implement this strategy, polar voxel basis functions were used to represent the object, resulting in a block-circulant system matrix. Simulation studies using a breast PET scanner model with ring geometry demonstrated improved contrast at 45% reduced noise level and 1.5 to 3 times resolution performance improvement when compared to MLEM reconstruction using a simple line-integral model. The GATE based system matrix reconstruction technique promises to improve resolution and noise performance and reduce image distortion at FOV periphery compared to line-integral based system matrix reconstruction.

  17. The ITERThe ITER eraera : the 10: the 10 yearyear roadmaproadmap for the French fusion programmefor the French fusion programme

    E-Print Network [OSTI]

    -2035 : The Fusion Energy Era of magnetic fusion research ITER thermonuclear plasmasITER thermonuclear plasmasThe ITERThe ITER eraera : the 10: the 10 yearyear roadmaproadmap for the French fusion programmefor the French fusion programme E. Tsitrone1 on behalf of IRFM and Tore Supra team 1 : CEA, IRFM, F-13108 Saint

  18. Exhibit 1C Patent Rights Retention by the Seller ITER UT-B Contracts Div Page 1 of 5

    E-Print Network [OSTI]

    Pennycook, Steve

    Exhibit 1C ­ Patent Rights ­ Retention by the Seller ­ ITER UT-B Contracts Div March 2007 Page 1 of 5 ex1c-ITER-mar07.doc Exhibit 1C ­ ITER Ref: DEAR 952.227-11 PATENT RIGHTS - RETENTION BY THE SELLER is or may be patentable or otherwise protectable under title 35 of the United States Code, or any novel

  19. Exhibit 1B Patent Rights Acquisition by the Government ITER UT-B Contracts Div Page 1 of 6

    E-Print Network [OSTI]

    Pennycook, Steve

    Exhibit 1B ­ Patent Rights ­ Acquisition by the Government ­ ITER UT-B Contracts Div March 2007 Page 1 of 6 ex1b-ITER-mar07.doc Exhibit 1B ITER Ref: DEAR 952.227-13 PATENT RIGHTS - ACQUISITION or discovery which is or may be patentable or otherwise protectable under title 35 of the United States Code

  20. Formation and Sustainment of ITPs in ITER with the Baseline Heating Mix

    SciTech Connect (OSTI)

    Francesca M. Poli and Charles Kessel

    2012-12-03T23:59:59.000Z

    Plasmas with internal transport barriers (ITBs) are a potential and attractive route to steady-state operation in ITER. These plasmas exhibit radially localized regions of improved con nement with steep pressure gradients in the plasma core, which drive large bootstrap current and generate hollow current pro les and negative shear. This work examines the formation and sustainment of ITBs in ITER with electron cyclotron heating and current drive. It is shown that, with a trade-o of the power delivered to the equatorial and to the upper launcher, the sustainment of steady-state ITBs can be demonstrated in ITER with the baseline heating con guration.

  1. Global integration of the Schr\\"odinger equation: a short iterative scheme within the wave operator formalism using discrete Fourier transforms

    E-Print Network [OSTI]

    Leclerc, Arnaud

    2015-01-01T23:59:59.000Z

    A global solution of the Schr\\"odinger equation for explicitly time-dependent Hamiltonians is derived by integrating the non-linear differential equation associated with the time-dependent wave operator. A fast iterative solution method is proposed in which, however, numerous integrals over time have to be evaluated. This internal work is done using a numerical integrator based on Fast Fourier Transforms (FFT). The case of a transition between two potential wells of a model molecule driven by intense laser pulses is used as an illustrative example. This application reveals some interesting features of the integration technique. Each iteration provides a global approximate solution on grid points regularly distributed over the full time propagation interval. Inside the convergence radius, the complete integration is competitive with standard algorithms, especially when high accuracy is required.

  2. Development Of a Spatially Resolving X-ray Crystal Spectrometer For Measurement Of Ion-temperature (Ti) And Rotation-velocity (v) Profiles in ITER

    SciTech Connect (OSTI)

    Hill, K W; Delgado-Aparico, L; Johnson, David; Feder, R; Beiersdorfer, P; Dunn, James; Morris, K; Wang, E; Reinke, M; Podpaly, Y; Rice, J E; Barnsley, R; O'Mullane, M

    2010-12-15T23:59:59.000Z

    Imaging x-ray crystal spectrometer #2;XCS#3; arrays are being developed as a US-ITER activity for Doppler measurement of Ti and v profiles of impurities #2;(W, Kr, and Fe)#3; with ~#4;7 cm (a/30)#3; and 10-100 ms resolution in ITER. The imaging XCS, modeled after a prototype instrument on Alcator C-Mod, uses a spherically bent crystal and 2D x-ray detectors to achieve high spectral resolving power (E / dE >#2;6000)#3; horizontally and spatial imaging vertically. Two arrays will measure Ti and both poloidal and toroidal rotation velocity profiles. The measurement of many spatial chords permits tomographic inversion for the inference of local parameters. The instrument design, predictions of performance, and results from C-Mod are presented.

  3. Development of a Spatially Resolving X-Ray Crystal Spectrometer (XCS) for Measurement of Ion-Temperature (Ti) and Rotation-Velocity (v) Profiles in ITER

    SciTech Connect (OSTI)

    Hill, K W; Delgado-Aprico, L; Johnson, D; Feder, R; Beiersdorfer,; Dunn, J; Morris, K; Wang, E; Reinke, M; Podpaly, Y; Rice, J E; Barnsley, R; O'Mullane, M; Lee, S G

    2010-05-21T23:59:59.000Z

    Imaging XCS arrays are being developed as a US-ITER activity for Doppler measurement of Ti and v profiles of impurities (W, Kr, Fe) with ~7 cm (a/30) and 10-100 ms resolution in ITER. The imaging XCS, modeled after a PPPL-MIT instrument on Alcator C-Mod, uses a spherically bent crystal and 2d x-ray detectors to achieve high spectral resolving power (E/dE>6000) horizontally and spatial imaging vertically. Two arrays will measure Ti and both poloidal and toroidal rotation velocity profiles. Measurement of many spatial chords permits tomographic inversion for inference of local parameters. The instrument design, predictions of performance, and results from C-Mod will be presented.

  4. Dilaton-scalar models in context of generalized affine gravity theories: their properties and integrability

    E-Print Network [OSTI]

    Davydov, E A

    2013-01-01T23:59:59.000Z

    Nowadays it is widely accepted that the evolution of the universe was driven by some scalar degrees of freedom both on its early stage and at present. The corresponding cosmological models often involve some scalar fields introduced ad hoc. In this paper we cultivate a different approach, which is based on a derivation of new scalar degrees of freedom from fundamental modifications of Einstein's gravity. In elaboration of our previous work, we here investigate properties of the dilaton-scalar gravity obtained by dimensional reductions of a recently proposed affine generalized gravity theory. We show that these models possess the same symmetries as related models of GR with ordinary scalar fields. As a result, for a rather general class of dilaton-scalar gravity models we construct additional first integrals and formulate an integral equation well suited for solving by iterations.

  5. Calculation and measurement of higher order mode losses in ITER ECH transmission lines

    E-Print Network [OSTI]

    Temkin, Richard J.

    The ITER transmission lines (TLs) must be designed to deliver 20 MW from a 24 MW, 170 GHz gyrotron system. Miter bends are the main source of loss for these highly overmoded, corrugated, cylindrical waveguide TLs. Previous ...

  6. Iterative equalization and decoding using reduced-state sequence estimation based soft-output algorithms

    E-Print Network [OSTI]

    Tamma, Raja Venkatesh

    2004-09-30T23:59:59.000Z

    We study and analyze the performance of iterative equalization and decoding (IED) using an M-BCJR equalizer. We use bit error rate (BER), frame error rate simulations and extrinsic information transfer (EXIT) charts to study and compare...

  7. Tritium inventory control in ITER Charles Skinner with key contributions from

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Tritium inventory control in ITER Charles Skinner with key contributions from Charles Gentile permitted" Tritium inventory control Worrisome issue: Once at the tritium limit there won't be any more

  8. ITERATIVE NEAR-FIELD (INF) PRECONDITIONER FOR THE MULTILEVEL FAST MULTIPOLE ALGORITHM

    E-Print Network [OSTI]

    Gürel, Levent

    ITERATIVE NEAR-FIELD (INF) PRECONDITIONER FOR THE MULTILEVEL FAST MULTIPOLE ALGORITHM LEVENT G in computa- tional electromagnetics using the multilevel fast multipole algorithm (MLFMA), preconditioners multipole method (FMM), multilevel fast multipole algorithm (MLFMA), sparse approximate inverse

  9. Joint News Release CHINA AND THE U.S. JOIN ITER NEGOTIATIONS

    E-Print Network [OSTI]

    the best working and living conditions. The EU Delegation also informed that the Spanish Secretary of State to personally re-iterate the firm commitment of all layers of Spanish government and society to the success

  10. Attachment to Joint Declaration of the Ministerial Meeting for ITER Moscow, 28th

    E-Print Network [OSTI]

    centre for fusion science a centre for remote experimentation - Fusion power plant technology co include: - IFMIF (EVEDA and/or facility) - ITER research centre(s): including, a computational simulation

  11. Performance of Closed Form and Iterative MU-MIMO Precoders for Different Broadcast

    E-Print Network [OSTI]

    Gesbert, David

    in improving both reliability and capacity of the system. Some theoretical analysis of the capacity, and Hassibi) algorithm proposed in [12] as it is an iterative algorithm for MU-MISO sumrate maximization based

  12. Print this article Close This Window EU OKs India joining ITER nuclear reactor project

    E-Print Network [OSTI]

    Print this article Close This Window EU OKs India joining ITER nuclear reactor project Fri Dec 2 trademarks and trademarks of the Reuters group of companies around the world. Close This Window 12/2/05 4

  13. Iterative receivers for OFDM systems with dispersive fading and frequency offset

    E-Print Network [OSTI]

    Liu, Hui

    2004-09-30T23:59:59.000Z

    The presence of dispersive fading and inter-carrier interference (ICI) constitute the major impediment to reliable communications in orthogonal frequency-division multiplexing (OFDM) systems. Recently iterative (``Turbo'') processing techniques...

  14. An assessment of the base blanket for ITER

    SciTech Connect (OSTI)

    Raffray, A.R.; Abdou, M.A.; Ying, A.

    1991-01-01T23:59:59.000Z

    Ideally, the ITER base blanket would provide the necessary tritium for the reactor to be self-sufficient during operation, while having minimal impact on the overall reactor cost, reliability and safety. A solid breeder blanket has been developed in CDA phase in an attempt to achieve such objectives. The reference solid breeder base blanket configurations at the end of the CDA phase has many attractive features such as a tritium breeding ratio (TBR) of 0.8--0.9 and a reasonably low tritium inventory. However, some concerns regarding the risk, cost and benefit of the base blanket have been raised. These include uncertainties associated with the solid breeder thermal control and the potentially high cost of the amount of Be used to achieve high TBR and to provide the necessary thermal barrier between the high temperature solid breeder and low temperature coolant. This work addresses these concerns. The basis for the selection of a breeding blanket is first discussed in light of the incremental risk, cost and benefits relative to a non-breeding blanket. Key issues associated with the CDA breeding blanket configurations are then analyzed. Finally, alternative schemes that could enhance the attractiveness and flexibility of a breeding blanket are explored.

  15. Helium-cooled solid breeder blanket for ITER

    SciTech Connect (OSTI)

    Raffray, A.R.; Abdou, M.A.; Chou, P.; Gorbis, Z.; Tillack, M.; Watanabe, Y.; Ying, A.

    1989-03-01T23:59:59.000Z

    This paper summarizes the latest results of a design study of a helium-cooled solid breeder blanket for ITER. Attractive features of this design include the following: (1) There is a significant design margin since only part of the allowable solid breeder temperature window needs to be used. (2) There is an expanding data base available from solid breeder experiments carried out internationally. (3) The solid breeder can be designed to operate at high reactor-relevant temperature, while the helium is kept at moderate temperature and pressure for safety and reliability. In addition, since helium is a gas, it can be run so as to optimize the structure temperature and accommodate long term power variation without incurring any substantial pressure penalty. (4) The use of helium, an inert gas minimizing any chemical reaction and corrosion, in combination with a low activation solid breeder, is a safety advantage. An extensive list of the blanket operating parameters is provided and key factors are discussed.

  16. An Overview of the US DCLL ITER-TBM Program

    SciTech Connect (OSTI)

    C.P.C. Wong; M. Abdou; M. Dagher; Y. Katoh; B. J. Merrill

    2010-12-01T23:59:59.000Z

    Under the US Fusion Nuclear Science and Technology program, we selected the Dual Coolant Lead Lithium (DCLL) concept as our primary Test Blanket Module (TBM) for testing in ITER. The DCLL blanket concept has the potential to be a high-performance DEMO blanket design with a projected thermal efficiency of >40%. Reduced activation ferritic/martensitic (RAF/M) steel is used as the structural material. Helium is used to cool the first wall and blanket structure, and the self-cooled Pb-17Li breeder is circulated for power conversion and for tritium extraction. A SiC-based flow channel insert (FCI) is used as an electrical insulator for magnetohydrodynamic pressure drop reduction from the circulating Pb-17Li and as a thermal insulator to separate the high-temperature Pb-17Li (650–700 °C) from the RAF/M structure, which has a corrosion temperature limit of 480 °C. The RAF/M material must also operate at temperatures above 350 °C but less than 550 °C. We are continuing the development of the mechanical design and performing neutronics, structural and thermal hydraulics analyses of the DCLL TBM module. Prototypical FCI structures were fabricated and further attention was paid to MHD effects and the design of the inboard blanket for DEMO. We are also making progress on related R&D needs to address key areas. This paper is a summary report on the progress and results of recent DCLL TBM development activities.

  17. An overview of the US DCLL ITER-TBM program

    SciTech Connect (OSTI)

    Wong, Clement; Abdou, Mohamed A.; Dagher, Mohamad; Katoh, Yutai; Kurtz, Richard J.; Malang, S.; Marriott, Edward P.; Merrill, Brad; Messadek, Karim; Morley, Neil; Sawan, M.; Sharafat, Shahran; Smolentsev, S.; Sze, Dai Kai; Willms, Scott; Ying, A. Y.; Youssef, M.

    2010-12-01T23:59:59.000Z

    Under the US Fusion Nuclear Science and Technology program, we selected the Dual Coolant Lead Lithium (DCLL) concept as our primary Test Blanket Module (TBM) for testing in ITER. The DCLL blanket concept has the potential to be a high-performance DEMO blanket design with a projected thermal ef?ciency of >40%. Reduced activation ferritic/martensitic (RAF/M) steel is used as the structural material. Helium is used to cool the ?rst wall and blanket structure, and the self-cooled Pb-17Li breeder is circulated for power conversion and for tritium extraction. A SiC-based ?ow channel insert (FCI) is used as an electrical insulator for magnetohydrodynamic pressure drop reduction from the circulating Pb-17Li and as a ther- mal insulator to separate the high-temperature Pb-17Li (?650–700 ? C) from the RAF/M structure, which has a corrosion temperature limit of ?480 ? C. The RAF/M material must also operate at temperatures above 350 ? C but less than 550 ? C. We are continuing the development of the mechanical design and per- forming neutronics, structural and thermal hydraulics analyses of the DCLL TBM module. Prototypical FCI structures were fabricated and further attention was paid to MHD effects and the design of the inboard blanket for DEMO. We are also making progress on related R&D needs to address key areas. This paper is a summary report on the progress and results of recent DCLL TBM development activities.

  18. An Overview of the US DCLL ITER TBM Program

    SciTech Connect (OSTI)

    Wong, C. P. C. [General Atomics, San Diego; Abdou, M [University of California, Los Angeles; Dagher, M [University of California, Los Angeles; Katoh, Yutai [ORNL; Kurtz, Richard [Pacific Northwest National Laboratory (PNNL); Malang, Siegfried [Consultant; Marriott, Edward [University of Wisconsin, Madison; Merrill, Brad [Idaho National Laboratory (INL); Messadek, K [University of California, Los Angeles; Morley, N.B. [University of California, Los Angeles; Pint, Bruce A [ORNL; Sawan, M. [University of Wisconsin; Sharafat, S [University of California, Los Angeles; Smolentsev, Sergey [University of California, Los Angeles; Sze, Dai-Kai [University of California, San Diego; Willms, Scott [Los Alamos National Laboratory (LANL); Ying, Alice [University of California, Los Angeles; Youssef, M Z [University of California, Los Angeles

    2010-01-01T23:59:59.000Z

    Under the US Fusion Nuclear Science and Technology program, we selected the Dual Coolant Lead Lithium (DCLL) concept as our primary Test Blanket Module (TBM) for testing in ITER. The DCLL blanket concept has the potential to be a high-performance DEMO blanket design with a projected thermal efficiency of >40%. Reduced activation ferritic/martensitic (RAF/M) steel is used as the structural material. Helium is used to cool the first wall and blanket structure, and the self-cooled Pb-17Li breeder is circulated for power conversion and for tritium extraction. A SiC-based flow channel insert (FCI) is used as an electrical insulator for magnetohydrodynamic pressure drop reduction from the circulating Pb-17Li and as a thermal insulator to separate the high-temperature Pb-17Li ({approx}650-700 C) from the RAF/M structure, which has a corrosion temperature limit of {approx}480 C. The RAF/M material must also operate at temperatures above 350 C but less than 550 C. We are continuing the development of the mechanical design and performing neutronics, structural and thermal hydraulics analyses of the DCLL TBM module. Prototypical FCI structures were fabricated and further attention was paid to MHD effects and the design of the inboard blanket for DEMO. We are also making progress on related R&D needs to address key areas. This paper is a summary report on the progress and results of recent DCLL TBM development activities.

  19. An assessment of the base blanket for ITER

    SciTech Connect (OSTI)

    Raffray, A.R.; Abdou, M.A.; Ying, A.

    1991-12-31T23:59:59.000Z

    Ideally, the ITER base blanket would provide the necessary tritium for the reactor to be self-sufficient during operation, while having minimal impact on the overall reactor cost, reliability and safety. A solid breeder blanket has been developed in CDA phase in an attempt to achieve such objectives. The reference solid breeder base blanket configurations at the end of the CDA phase has many attractive features such as a tritium breeding ratio (TBR) of 0.8--0.9 and a reasonably low tritium inventory. However, some concerns regarding the risk, cost and benefit of the base blanket have been raised. These include uncertainties associated with the solid breeder thermal control and the potentially high cost of the amount of Be used to achieve high TBR and to provide the necessary thermal barrier between the high temperature solid breeder and low temperature coolant. This work addresses these concerns. The basis for the selection of a breeding blanket is first discussed in light of the incremental risk, cost and benefits relative to a non-breeding blanket. Key issues associated with the CDA breeding blanket configurations are then analyzed. Finally, alternative schemes that could enhance the attractiveness and flexibility of a breeding blanket are explored.

  20. Status of the Design of the ITER ECE Diagnostic

    SciTech Connect (OSTI)

    Taylor, Gary [PPPL

    2014-04-01T23:59:59.000Z

    The baseline design for the ITER electron cyclotron emission (ECE) diagnostic has entered the detailed preliminary design phase. Two plasma views are planned, a radial view and an oblique view that is sensitive to distortions in the electron momentum distribution near the average thermal momentum. Both views provide high spatial resolution electron temperature profiles when the momentum distribution remains Maxwellian. The ECE diagnostic system consists of the front-end optics, including two 1000 K calibration sources, in equatorial port plug EP9, the 70-1000 GHz transmission system from the front-end to the diagnostics hall, and the ECE instrumentation in the diagnostics hall. The baseline ECE instrumentation will include two Michelson interferometers that can simultaneously measure ordinary and extraordinary mode ECE from 70 to 1000 GHz, and two heterodyne radiometer systems, covering 122-230 GHz and 244-355 GHz. Significant design challenges include 1) developing highly-reliable 1000 K calibration sources and the associated shutters/mirrors, 2) providing compliant couplings between the front-end optics and the polarization splitter box that accommodate displacements of the vacuum vessel during plasma operations and bake out, 3) protecting components from damage due to stray ECH radiation and other intense millimeter wave emission and 4) providing the low-loss broadband transmission system.

  1. Code of a Tokamak Fusion Energy Facility ITER

    SciTech Connect (OSTI)

    Yasuhide Asada [Central Research Institute of Electric Power Industry - CRIEPI (Japan); Kenzo Miya [Keio University (Japan); Kazuhiko Hada; Eisuke Tada [Japan Atomic Energy Research Institute (Japan)

    2002-07-01T23:59:59.000Z

    The technical structural code for ITER (International Thermonuclear Experimental Fusion Reactor) and, as more generic applications, for D-T burning fusion power facilities (hereafter, Fusion Code) should be innovative because of their quite different features of safety and mechanical components from nuclear fission reactors, and the necessity of introducing several new fabrication and examination technologies. Introduction of such newly developed technologies as inspection-free automatic welding into the Fusion Code is rationalized by a pilot application of a new code concept of {sup s}ystem-based code for integrity{sup .} The code concept means an integration of element technical items necessary for construction, operation and maintenance of mechanical components of fusion power facilities into a single system to attain an optimization of the total margin of these components. Unique and innovative items of the Fusion Code are typically as follows: - Use of non-metals; - Cryogenic application; - New design margins on allowable stresses, and other new design rules; - Use of inspection-free automatic welding, and other newly developed fabrication technologies; - Graded approach of quality assurance standard to cover radiological safety-system components as well as non-safety-system components; - Consideration on replacement components. (authors)

  2. Design and RF measurements of a 5 GHz 500 kW window for the ITER LHCD system

    E-Print Network [OSTI]

    Hillairet, Julien; Dechambre, N; Delpech, L; Ekedahl, A; Faure, N; Goniche, M; Kim, J; Larroque, S; Magne, R; Marfisi, L; Namkung, W; Park, H; Park, S; Poli, S; Vulliez, K

    2015-01-01T23:59:59.000Z

    CEA/IRFM is conducting R\\&D efforts in order to validate the critical RF components of the 5 GHz ITER LHCD system, which is expected to transmit 20 MW of RF power to the plasma. Two 5 GHz 500 kW BeO pill-box type window prototypes have been manufactured in 2012 by the PMB Company, in close collaboration with CEA/IRFM. Both windows have been validated at low power, showing good agreement between measured and modeling, with a return loss better than 32 dB and an insertion loss below 0.05 dB. This paper reports on the window RF design and the low power measurements. The high power tests up to 500kW have been carried out in March 2013 in collaboration with NFRI. Results of these tests are also reported. In the current ITER LHCD design, 20 MW Continuous Wave (CW) of Radio-Frequency power at 5 GHz are expected to be generated and transmitted to the plasma. In order to separate the vacuum vessel pressure from the cryostat waveguide pressure, forty eight 5 GHz 500kW CW windows are to be assembled on the waveguide...

  3. PHYSICS AND CONTROL OF ELMING H-MODE NEGATIVE CENTRAL SHEAR ADVANCED TOKAMAK SCENARIO BASED ON EXPERIMENTAL PROFILES FOR ITER

    SciTech Connect (OSTI)

    LAO,LL; CHAN,VS; EVANS,TE; HUMPHREYS,DA; LEUER,JA; MAHDAVI,MA; PETRIE,TW; SNYDER,PB; STJOHN,HE; STAEBLER,GM; STAMBAUGH,RD; TAYLOR,TS; TURNBULL,AD; WEST,WP; BRENNAN,DP

    2002-11-01T23:59:59.000Z

    A271 PHYSICS AND CONTROL OF ELMING H-MODE NEGATIVE CENTRAL SHEAR ADVANCED TOKAMAK SCENARIO BASED ON EXPERIMENTAL PROFILES FOR ITER. Key DIII-D AT experimental and modeling results are applied to examine the physics and control issues for ITER to operate in a negative central shear (NCS) AT scenario. The effects of a finite edge pressure pedestal and current density are included based on the DIII-D experimental profiles. Ideal and resistive stability analyses indicate that feedback control of resistive wall modes by rotational drive or flux conserving intelligent coils is crucial for these AT configurations to operate at attractive {beta}{sub N} values in the range of 3.0-3.5. Vertical stability and halo current analyses show that reliable disruption mitigation is essential and mitigation control using an impurity gas can significantly reduce the local mechanical stress to an acceptable level. Core transport and turbulence analyses demonstrate that control of the rotational shear profile is essential to maintain the good confinement necessary for high {beta}. Consideration of edge stability and core transport suggests that a sufficiently wide pedestal is necessary for the projected fusion performance. Heat flux analyses indicate that with core-only radiation enhancement the outboard peak divertor heat load is near the design limit of 10 MW/m{sup 2}

  4. ITER as a Physics Experiment K.Lackner, D. Campbell and many others

    E-Print Network [OSTI]

    : -> only full CD,ELMy H-mode cases shown JT-60U RS JT-60U high bp ITER & Power Plant: higher n-mode access, ELMs, NTMs..) · qualify a-particle heating as a heating method · high power/long pulse (on wall of sawteeth (JET) AUG DIII- D #12;Q =10: ITER-simulation discharges on JET JET-operating space #12;Q =10

  5. Qualification of the US made conductors for ITER TF magnet system

    SciTech Connect (OSTI)

    Martovetsky, N; Hatfield, D; Miller, J; Bruzzone, P; Stepanov, B; Seber, B

    2009-10-08T23:59:59.000Z

    The US Domestic Agency (USDA) is one of the six suppliers of the TF conductor for ITER. In order to qualify conductors according to ITER requirements we prepared several lengths of the CICC and short samples for testing in the SULTAN facility in CRPP, Switzerland. We also fully characterized the strands that were used in these SULTAN samples. Fabrication experience and test results are presented and discussed.

  6. Adaptive Mesh Refinement and Multilevel Iteration for Flow in Porous Media

    E-Print Network [OSTI]

    Trangenstein, John A.

    are provided. #12; 1 Introduction. The numerical treatment of field­scale simulation of enhanced oil recovery in diameter and involve hundreds of wells. Also, fluid models used in enhanced oil recovery often encompass­ tion is a formidable task. To provide useful information for the development of recovery processes

  7. FEMCAM Analysis of SULTAN Test Results for ITER Nb3SN Cable-conduit Conductors

    SciTech Connect (OSTI)

    Yuhu Zhai, Pierluigi Bruzzone, Ciro Calzolaio

    2013-03-19T23:59:59.000Z

    Performance degradation due to filament fracture of Nb3 Sn cable-in-conduit conductors (CICCs) is a critical issue in large-scale magnet designs such as ITER which is currently being constructed in the South of France. The critical current observed in most SULTAN TF CICC samples is significantly lower than expected and the voltage-current characteristic is seen to have a much broader transition from a single strand to the CICC. Moreover, most conductors exhibit the irreversible degradation due to filament fracture and strain relaxation under electromagnetic cyclic loading. With recent success in monitoring thermal strain distribution and its evolution under the electromagnetic cyclic loading from in situ measurement of critical temperature, we apply FEMCAM which includes strand filament breakage and local current sharing effects to SULTAN tested CICCs to study Nb3 Sn strain sensitivity and irreversible performance degradation. FEMCAM combines the thermal bending effect during cool down and the EM bending effect due to locally accumulating Lorentz force during magnet operation. It also includes strand filament fracture and related local current sharing for the calculation of cable n value. In this paper, we model continuous performance degradation under EM cyclic loading based on strain relaxation and the transition broadening upon cyclic loading to the extreme cases seen in SULTAN test data to better quantify conductor performance degradation.

  8. Operation and coupling of LH waves with the ITER-like wall at JET

    E-Print Network [OSTI]

    Kirov, K K; Ekedahl, A; Petrzilka, V; Arnoux, G; Baranov, Yu; Brix, M; Goniche, M; Jachmich, S; Mayoral, M-L; Ongena, J; Rimini, F; Stamp, M; Contributors, JET EFDA

    2013-01-01T23:59:59.000Z

    In this paper important aspects of Lower Hybrid (LH) operation with the ITER Like Wall (ILW) [1] at JET are reported. Impurity release during LH operation was investigated and it was found that there is no significant Be increase with LH power. Concentration of W was analysed in more detail and it was concluded that LH contributes negligibly to its increase. No cases of W accumulation in LH-only heating experiments were observed so far. LH wave coupling was studied and optimised to achieve the level of system performance similar to before ILW installation. Measurements by Li-beam were used to study systematic dependencies of the SOL density on the gas injection rate from a dedicated gas introduction module and the LH power and launcher position. Experimental results are supported by SOL transport modelling. Observations of arcs in front of the LH launcher and hotspots on magnetically connected sections of the vessel are reported. Overall, a relatively troublefree operation of the LH system up to 2.5MW of coup...

  9. Nonparametric GARCH Models Peter Buhlmann

    E-Print Network [OSTI]

    McNeil, Alexander J.

    Nonparametric GARCH Models Peter Buhlmann #3; Seminar fur Statistik Federal Institute describe a nonparametric GARCH model of #12;rst order and pro- pose a simple iterative algorithm for its GARCH(1,1) modelling, particularly when asymmetries are present in the data. We show how the basic

  10. Design of fast tuning elements for the ITER ICH system

    SciTech Connect (OSTI)

    Swain, D.W.; Goulding, R.H.

    1996-05-01T23:59:59.000Z

    The coupling between the ion cyclotron (IC) antenna and the ITER plasma (as expressed by the load resistance the antenna sees) will experience relatively fast variations due to plasma edge profile modifications. If uncompensated, these will cause an increase in the amount of power reflected back to the transmitter and ultimately a decrease in the amount of radio frequency (rf) power to the plasma caused by protective suppression of the amount of rf power generated by the transmitter. The goals of this task were to study several alternate designs for a tuning and matching (T&M) system and to recommend some research and development (R&D) tasks that could be carried out to test some of the most promising concepts. Analyses of five different T&M configurations are presented in this report. They each have different advantages and disadvantages, and the choice among them must be made depending on the requirements for the IC system. Several general conclusions emerge from our study: The use of a hybrid splitter as a passive reflected-power dump [``edge localized mode (ELM)-dump``] appears very promising; this configuration will protect the rf power sources from reflected power during changes in plasma loading due to plasma motion or profile changes (e.g., ELM- induced changes in the plasma scrape-off region) and requires no active control of the rf system. Trade-offs between simplicity of design and capability of the system must be made. Simple system designs with few components near the antenna either have high voltages over considerable distances of transmission lines, or they are not easily tuned to operate at different frequencies. Designs using frequency shifts and/or fast tuning elements can provide fast matching over a wide range of plasma loading; however, the designs studied here require components near the antenna, complicating assembly and maintenance. Capacitor-tuned resonant systems may offer a good compromise.

  11. A high level meeting between the ITER Participants today in Vienna issued the following press release: "Common Message from the 5th Preparatory Meeting for ITER Decision Making

    E-Print Network [OSTI]

    th November 2005) High level negotiators from China, European Union, Japan, the Republic of Korea is currently Ambassador of Japan to Croatia, is a graduate Nuclear Engineer and has extensive experience ITER Agreement and completion of the Negotiations. Conclusion With the progress made in the Parties

  12. Cyber Incidents Involving Control Systems

    SciTech Connect (OSTI)

    Robert J. Turk

    2005-10-01T23:59:59.000Z

    The Analysis Function of the US-CERT Control Systems Security Center (CSSC) at the Idaho National Laboratory (INL) has prepared this report to document cyber security incidents for use by the CSSC. The description and analysis of incidents reported herein support three CSSC tasks: establishing a business case; increasing security awareness and private and corporate participation related to enhanced cyber security of control systems; and providing informational material to support model development and prioritize activities for CSSC. The stated mission of CSSC is to reduce vulnerability of critical infrastructure to cyber attack on control systems. As stated in the Incident Management Tool Requirements (August 2005) ''Vulnerability reduction is promoted by risk analysis that tracks actual risk, emphasizes high risk, determines risk reduction as a function of countermeasures, tracks increase of risk due to external influence, and measures success of the vulnerability reduction program''. Process control and Supervisory Control and Data Acquisition (SCADA) systems, with their reliance on proprietary networks and hardware, have long been considered immune to the network attacks that have wreaked so much havoc on corporate information systems. New research indicates this confidence is misplaced--the move to open standards such as Ethernet, Transmission Control Protocol/Internet Protocol, and Web technologies is allowing hackers to take advantage of the control industry's unawareness. Much of the available information about cyber incidents represents a characterization as opposed to an analysis of events. The lack of good analyses reflects an overall weakness in reporting requirements as well as the fact that to date there have been very few serious cyber attacks on control systems. Most companies prefer not to share cyber attack incident data because of potential financial repercussions. Uniform reporting requirements will do much to make this information available to Department of Homeland Security (DHS) and others who require it. This report summarizes the rise in frequency of cyber attacks, describes the perpetrators, and identifies the means of attack. This type of analysis, when used in conjunction with vulnerability analyses, can be used to support a proactive approach to prevent cyber attacks. CSSC will use this document to evolve a standardized approach to incident reporting and analysis. This document will be updated as needed to record additional event analyses and insights regarding incident reporting. This report represents 120 cyber security incidents documented in a number of sources, including: the British Columbia Institute of Technology (BCIT) Industrial Security Incident Database, the 2003 CSI/FBI Computer Crime and Security Survey, the KEMA, Inc., Database, Lawrence Livermore National Laboratory, the Energy Incident Database, the INL Cyber Incident Database, and other open-source data. The National Memorial Institute for the Prevention of Terrorism (MIPT) database was also interrogated but, interestingly, failed to yield any cyber attack incidents. The results of this evaluation indicate that historical evidence provides insight into control system related incidents or failures; however, that the limited available information provides little support to future risk estimates. The documented case history shows that activity has increased significantly since 1988. The majority of incidents come from the Internet by way of opportunistic viruses, Trojans, and worms, but a surprisingly large number are directed acts of sabotage. A substantial number of confirmed, unconfirmed, and potential events that directly or potentially impact control systems worldwide are also identified. Twelve selected cyber incidents are presented at the end of this report as examples of the documented case studies (see Appendix B).

  13. ITER Building Design (D230-B), Task No. 28. Final report

    SciTech Connect (OSTI)

    NONE

    1995-12-01T23:59:59.000Z

    The International Thermonuclear Experimental Reactor (ITER) Project requires a set of buildings, each with its own distinct function, to support ITER`s mission. The Joint Central Team (JCT) has identified all the buildings in the set and has placed them in an efficient arrangement on the site. The JCT has developed a conceptual layout of each individual building. The buildings have been categorized into two main groups: (1) {open_quotes}Level 1 Buildings{close_quotes} which are on the construction schedule critical path and (2) {open_quotes}Level 2 Buildings{close_quotes} which, while important, are not on the critical path. The buildings are further categorized according to construction material, that is, {open_quotes}reinforced concrete{close_quotes} or {open_quotes}steel-frame on concrete slab{close_quotes}. This Report responds to the Project`s request to perform the initial structural steel design for all the {open_quotes}steel-frame on concrete slab{close_quotes} buildings. Of the twelve (12) {open_quotes}steel-frame on concrete slab{close_quotes} buildings, four (4) are Level 1 and eight (8) are Level 2 Buildings. This Report is a deliverable for the ITER Task Assignment entitled {open_quotes}ITER Buildings Design (D230-B){close_quotes}, also designated as Task No. 28. ITER U.S. Home Team Industrial Consortium members, Raytheon Engineers & Constructors (RE&C) and Stone & Webster Engineering Corporation (SWEC), teamed to perform Task 28. This task commenced in May 1995. It was performed in accordance with the design criteria specified by the ITER-JCT, San Diego Joint Work Site.

  14. Studies involving low protein broiler diets

    E-Print Network [OSTI]

    Parkin, David Palmer

    1971-01-01T23:59:59.000Z

    STUDIES INVOLVING L(% PROTEIN BROILER DIETS A Thesis by David Palmer Parkin Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE May 1971 Major Subject...: Poultry Science STUDIES INVOLVING LS& PROTEIN BROILER DIETS A Thesis by David Palmer Parkin Approved as to style and content by: (Chairman of Commit e) ead of. Departmen Me er) (Member) (Memb ) May 1971 ABSTRACT Studies Involving Low Protein...

  15. DCLL TBM Safety Assessment A key objective for ITER includes integrated testing of blanket concepts suitable for demonstrating fusion

    E-Print Network [OSTI]

    prototypical blanket modules into designated ports. Because ITER will be a licensed nuclear facility, occupation radiation exposure (ORE) analyzed, and decommissioning and waste disposal analysis performed

  16. The Leadership and Involvement Record Sponsored by the Center for Leadership and Involvement

    E-Print Network [OSTI]

    Sheridan, Jennifer

    The Leadership and Involvement Record Sponsored by the Center for Leadership and Involvement The Leadership and Involvement Record is an official document from the University of Wisconsin recording the leadership roles, student org involvement, or group membership students have had on campus. The record

  17. ITER vacuum vessel fabrication plan and cost study (D 68) for the international thermonuclear experimental reactor

    SciTech Connect (OSTI)

    NONE

    1995-01-01T23:59:59.000Z

    ITER Task No. 8, Vacuum Vessel Fabrication Plan and Cost Study (D68), was initiated to assess ITER vacuum vessel fabrication, assembly, and cost. The industrial team of Raytheon Engineers & Constructors and Chicago Bridge & Iron (Raytheon/CB&I) reviewed the current vessel basis and prepared a manufacturing plan, assembly plan, and cost estimate commensurate with the present design. The guidance for the Raytheon/CB&I assessment activities was prepared by the ITER Garching Work Site. This guidance provided in the form of work descriptions, sketches, drawings, and costing guidelines for each of the presently identified vacuum vessel Work Breakdown Structure (WBS) elements was compiled in ITER Garching Joint Work Site Memo (Draft No. 9 - G 15 MD 01 94-17-05 W 1). A copy of this document is provided as Appendix 1 to this report. Additional information and clarifications required for the Raytheon/CB&I assessments were coordinated through the US Home Team (USHT) and its technical representative. Design details considered essential to the Task 8 assessments but not available from the ITER Joint Central Team (JCT) were generated by Raytheon/CB&I and documented accordingly.

  18. Pellet injection into H-mode ITER plasma with the presence of internal transport barriers

    SciTech Connect (OSTI)

    Leekhaphan, P. [Thammasat University, School of Bio-Chemical Engineering and Technology, Sirindhorn International Institute of Technology (Thailand); Onjun, T. [Thammasat University, School of Manufacturing Systems and Mechanical Engineering, Sirindhorn International Institute of Technology (Thailand)

    2011-04-15T23:59:59.000Z

    The impacts of pellet injection into ITER type-1 ELMy H-mode plasma with the presence of internal transport barriers (ITBs) are investigated using self-consistent core-edge simulations of 1.5D BALDUR integrated predictive modeling code. In these simulations, the plasma core transport is predicted using a combination of a semi-empirical Mixed B/gB anomalous transport model, which can self-consistently predict the formation of ITBs, and the NCLASS neoclassical model. For simplicity, it is assumed that toroidal velocity for {omega}{sub E Multiplication-Sign B} calculation is proportional to local ion temperature. In addition, the boundary conditions are predicted using the pedestal temperature model based on magnetic and flow shear stabilization width scaling; while the density of each plasma species, including both hydrogenic and impurity species, at the boundary are assumed to be a large fraction of its line averaged density. For the pellet's behaviors in the hot plasma, the Neutral Gas Shielding (NGS) model by Milora-Foster is used. It was found that the injection of pellet could result in further improvement of fusion performance from that of the formation of ITB. However, the impact of pellet injection is quite complicated. It is also found that the pellets cannot penetrate into a deep core of the plasma. The injection of the pellet results in a formation of density peak in the region close to the plasma edge. The injection of pellet can result in an improved nuclear fusion performance depending on the properties of pellet (i.e., increase up to 5% with a speed of 1 km/s and radius of 2 mm). A sensitivity analysis is carried out to determine the impact of pellet parameters, which are: the pellet radius, the pellet velocity, and the frequency of injection. The increase in the pellet radius and frequency were found to greatly improve the performance and effectiveness of fuelling. However, changing the velocity is observed to exert small impact.

  19. Iterative prediction of chaotic time series using a recurrent neural network. Quarterly progress report, January 1, 1995--March 31, 1995

    SciTech Connect (OSTI)

    Bodruzzaman, M.; Essawy, M.A.

    1996-03-31T23:59:59.000Z

    Chaotic systems are known for their unpredictability due to their sensitive dependence on initial conditions. When only time series measurements from such systems are available, neural network based models are preferred due to their simplicity, availability, and robustness. However, the type of neural network used should be capable of modeling the highly non-linear behavior and the multi- attractor nature of such systems. In this paper we use a special type of recurrent neural network called the ``Dynamic System Imitator (DSI)``, that has been proven to be capable of modeling very complex dynamic behaviors. The DSI is a fully recurrent neural network that is specially designed to model a wide variety of dynamic systems. The prediction method presented in this paper is based upon predicting one step ahead in the time series, and using that predicted value to iteratively predict the following steps. This method was applied to chaotic time series generated from the logistic, Henon, and the cubic equations, in addition to experimental pressure drop time series measured from a Fluidized Bed Reactor (FBR), which is known to exhibit chaotic behavior. The time behavior and state space attractor of the actual and network synthetic chaotic time series were analyzed and compared. The correlation dimension and the Kolmogorov entropy for both the original and network synthetic data were computed. They were found to resemble each other, confirming the success of the DSI based chaotic system modeling.

  20. Quantum mechanical Hamiltonian models of discrete processes that erase their own histories: application to Turing machines

    SciTech Connect (OSTI)

    Benioff, P.A.

    1981-01-01T23:59:59.000Z

    Work done before on the construction of quantum mechanical Hamiltonian models of Turing machines and general descrete processes is extended here to include processes which erase their own histories. The models consist of three phases, the forward process phase in which a map T is iterated and a history of iterations is generated, a copy phase which is activated if and only if T reaches a fix point, and an erase phase which erases the iteration history, undoes the iterations of T and recovers the initial state except for the copy system. A ballast system is used to stop the evolution at the desired state. The general model so constructed is applied to Turing machines. The main changes are that the system undergoing the evolution corresponding to T iterations becomes three systems corresponding to the internal machine, the computation tape, and computation head. Also the copy phase becomes more complex since it is desired that this correspond also to a copying Turing machine.

  1. Graphic Designer Student Involvement and Leadership

    E-Print Network [OSTI]

    Subramanian, Venkat

    Graphic Designer Student Involvement and Leadership Position Overview The Graphic Designer standards of the Student Involvement and Leadership brand guardrails · Complete other duties as assigned-Design, and Illustrator · Must have experience creating print and web graphics, flyers, and other promotional materials

  2. Prefrontal involvement in the regulation of emotion: convergence of rat and human studies

    E-Print Network [OSTI]

    Quirk, Gregory J.

    experiments designed to bridge human and rodent models of emotion regulation. Addresses 1 Department of prefrontal involvement of emotion regula- tion using rat and human models, and suggest future experimentsPrefrontal involvement in the regulation of emotion: convergence of rat and human studies Gregory J

  3. Experimental Results with the New ITER-like 1 MV SINGAP Accelerator

    SciTech Connect (OSTI)

    Svensson, L.; Esch, H.P.L. de; Hemsworth, R.S.; Massmann, P. [Association EURATOM-CEA, CEA/DSM/DRFC, CEA -Cadarache, 13108 St Paul-lez-Durance (France); Boilson, D. [Association EURATOM-DCU, PRL/NCPST, Glasnevin, Dublin 13 (Ireland)

    2005-04-06T23:59:59.000Z

    A new 'ITER-like' accelerator, which is a scaled down version of the ITER SINGAP (SINgle GAP, SINGle APerture) accelerator, has been built and installed on the Cadarache 1 MV test bed. The objective is to demonstrate reliable D- beam acceleration as close as possible to 1 MeV with a current density j- {approx_equal} 200 A/m2 with the beam optics required for ITER, i.e. a beamlet divergence of {<=}7 mrad and beamlet steering within {+-}2 mrad of that specified. High voltage hold off tests have been performed and 940 kV has been held without breakdowns. The first beams up to 850 keV (D-, 15 A/m2) have been obtained after 4 weeks of experiments and the highest current density that has been obtained so far is 85 A/m2 (D-, 580 keV)

  4. Pellet Fueling, ELM pacing, and Disruption Mitigation Technology Development for ITER

    SciTech Connect (OSTI)

    Baylor, Larry R [ORNL; Combs, Stephen Kirk [ORNL; Foust, Charles R [ORNL; Jernigan, Thomas C [ORNL; Meitner, S. J. [Oak Ridge National Laboratory (ORNL); Parks, P. B. [General Atomics; Caughman, John B [ORNL; Maruyama, S. [ITER International Team, Garching, Germany; Qualls, A L [ORNL; Rasmussen, David A [ORNL; ThomasJr., C. E. [Third Dimension Technologies, LLC, Knoxville, TN

    2009-01-01T23:59:59.000Z

    Plasma fueling with pellet injection, pacing of edge localized modes (ELMs) by small frequent pellets, and disruption mitigation with gas jets or injected pellets are some of the most important technological capabilities needed for successful operation of ITER. Tools are being developed at Oak Ridge National Laboratory that can be employed on ITER to provide the necessary core pellet fueling and the mitigation of ELMs and disruptions. Here we present progress on the development of the technology to provide reliable high throughput inner wall pellet fueling, pellet ELM pacing with high frequency small pellets, and disruption mitigation with gas jets and pellets. Examples of how these tools can be employed on ITER are discussed.

  5. Tungsten spectroscopy relevant to the diagnostics development of ITER divertor plasmas

    SciTech Connect (OSTI)

    Clementson, J; Beiersdorfer, P; Magee, E W; McLean, H S; Wood, R D

    2009-12-01T23:59:59.000Z

    The ITER tokamak will have tungsten divertor tiles and, consequently, the divertor plasmas are expected to contain tungsten ions. The spectral emission from these ions can serve to diagnose the divertor for plasma parameters such as tungsten concentrations, densities, ion and electron temperatures, and flow velocities. The ITER divertor plasmas will likely have densities around 10{sup 14-15} cm{sup -3} and temperatures below 150 eV. These conditions are similar to the plasmas at the Sustained Spheromak Physics Experiment (SSPX) in Livermore. To simulate ITER divertor plasmas, a tungsten impurity was introduced into the SSPX spheromak by prefilling it with tungsten hexacarbonyl prior to the usual hydrogen gas injection and initiation of the plasma discharge. The possibility of using the emission from low charge state tungsten ions to diagnose tokamak divertor plasmas has been investigated using a high-resolution extreme ultraviolet spectrometer.

  6. SOFTWARE EVOLUTION AND THE STAGED MODEL OF THE SOFTWARE LIFECYCLE

    E-Print Network [OSTI]

    1 SOFTWARE EVOLUTION AND THE STAGED MODEL OF THE SOFTWARE LIFECYCLE K. H. Bennett Research............................................................................................................11 1.5 Iterative software development ...............................................................................................................19 1.10 The stages of the software lifecycle

  7. TRANSP Tests Of TGLF and Predictions For ITER

    SciTech Connect (OSTI)

    Robert V Budny, et al

    2013-06-02T23:59:59.000Z

    Gyro kinetic simulations of turbulence capture some of the features observed in transport, fluctuations, and correlations measured in tokamak plasmas. These codes calculations are CPU intensive, and are not practical for incorporation in present time-dependant transport codes, so reduced models based on these gyro kinetic codes are being used. An example is the TGLF model [1] which is a quasilinear gyrofluid model calibrated to nonlinear results from the GYRO code [2]. Recently TGLF has been incorporated into TRANSP [3].

  8. Review of ITER Physics Issues and Possible Approaches to their Solution

    E-Print Network [OSTI]

    to Reversed Shear qMIN 1.0 - 1. 8 >2.0 qEDGE 3 3.5-5 4-5 Sawteeth Present, Sought Absent, 3/2 mode t p * t R t W G=H89PN/q95 2=0.5-0.4, q95~3.4 G=0.75 Weak Shear High & AT (self regulating) regime > R to ITER · ITER Baseline- Conventional Sawtoothing, Elming H-mode ­ Conservative route to 500 MW, 400

  9. Bounds on the map threshold of iterative decoding systems with erasure noise

    E-Print Network [OSTI]

    Wang, Chia-Wen

    2008-10-10T23:59:59.000Z

    node is l+1i = f( l1; l2; :::; li 1; li+1; :::; ldc); where l+1i is the message passed from check node to bit node for degree type i and iteration l + 1. li is the message passed from bit node to check node for degree type i and iteration l. From... the right in Fig. 2, message sent along the edge from the bit node to the check node is l+1i = g( l1; l2; :::; li 1; li+1; :::; ldc): For the case of transmission over a binary channel, the messages can be com- pressed to a single real quantity...

  10. Electromagnetic Analysis For The Design Of ITER Diagnostic Port Plugs During Plasma Disruptions

    SciTech Connect (OSTI)

    Zhai, Y

    2014-03-03T23:59:59.000Z

    ITER diagnostic port plugs perform many functions including structural support of diagnostic systems under high electromagnetic loads while allowing for diagnostic access to plasma. The design of diagnotic equatorial port plugs (EPP) are largely driven by electromagnetic loads and associate response of EPP structure during plasma disruptions and VDEs. This paper summarizes results of transient electromagnetic analysis using Opera 3d in support of the design activities for ITER diagnostic EPP. A complete distribution of disruption loads on the Diagnostic First Walls (DFWs). Diagnostic Shield Modules (DSMs) and the EPP structure, as well as impact on the system design integration due to electrical contact among various EPP structural components are discussed.

  11. Beyond ITER: Neutral beams for a demonstration fusion reactor (DEMO) (invited)

    SciTech Connect (OSTI)

    McAdams, R., E-mail: roy.mcadams@ccfe.ac.uk [EURATOM/CCFE Association, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB (United Kingdom)

    2014-02-15T23:59:59.000Z

    In the development of magnetically confined fusion as an economically sustainable power source, International Tokamak Experimental Reactor (ITER) is currently under construction. Beyond ITER is the demonstration fusion reactor (DEMO) programme in which the physics and engineering aspects of a future fusion power plant will be demonstrated. DEMO will produce net electrical power. The DEMO programme will be outlined and the role of neutral beams for heating and current drive will be described. In particular, the importance of the efficiency of neutral beam systems in terms of injected neutral beam power compared to wallplug power will be discussed. Options for improving this efficiency including advanced neutralisers and energy recovery are discussed.

  12. ICRF heating in JET during initial operations with the ITER-like wall

    SciTech Connect (OSTI)

    Jacquet, P.; Brix, M.; Graham, M.; Mayoral, M.-L.; Meigs, A.; Monakhov, I.; Sirinelli, A. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Bobkov, V.; Drewelow, P.; Pütterich, T. [Max-Planck-Institut für Plasmaphysik, EURATOM-Assoziation, Garching (Germany); Brezinsek, S. [IEK-4, Forschungszentrum Jülich, Association EURATOM-FZJ (Germany); Campergue, A-L. [Ecole Nationale des Ponts et Chaussées, F77455 Marne-la-Vallée (France); Colas, L. [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Czarnecka, A. [Association Euratom-IPPLM, Hery 23, 01-497 Warsaw (Poland); Klepper, C. C. [Oak Ridge National Laboratory, Oak Ridge, TN 37831-6169 (United States); Lerche, E.; Van-Eester, D. [Association EURATOM-Belgian State, ERM-KMS, Brussels (Belgium); Milanesio, D. [Politecnico di Torino, Department of Electronics, Torino (Italy); Mlynar, J. [Association EURATOM-IPP.CR, Za Slovankou 3, 182 21 Praha 8 (Czech Republic); Collaboration: JET-EFDA Contributors

    2014-02-12T23:59:59.000Z

    In 2011/12, JET started operation with its new ITER-Like Wall (ILW) made of a tungsten (W) divertor and a beryllium (Be) main chamber wall. The impact of the new wall material on the JET Ion Cyclotron Resonance Frequency (ICRF) operation was assessed and also the properties of JET plasmas heated with ICRF were studied. No substantial change of the antenna coupling resistance was observed with the ILW as compared with the carbon wall. Heat-fluxes on the protecting limiters close the antennas quantified using Infra-Red (IR) thermography (maximum 4.5 MW/m{sup 2} in current drive phasing) are within the wall power load handling capabilities. A simple RF sheath rectification model using the antenna near-fields calculated with the TOPICA code can well reproduce the heat-flux pattern around the antennas. ICRF heating results in larger tungsten and nickel (Ni) contents in the plasma and in a larger core radiation when compared to Neutral Beam Injection (NBI) heating. Some experimental facts indicate that main-chamber W components could be an important impurity source: the divertor W influx deduced from spectroscopy is comparable when using RF or NBI at same power and comparable divertor conditions; the W content is also increased in ICRF-heated limiter plasmas; and Be evaporation in the main chamber results in a strong and long lasting reduction of the impurity level. The ICRF specific high-Z impurity content decreased when operating at higher plasma density and when increasing the hydrogen concentration from 5% to 20%. Despite the higher plasma bulk radiation, ICRF exhibited overall good plasma heating efficiency; The ICRF power can be deposited at plasma centre and the radiation is mainly from the outer part of the plasma. Application of ICRF heating in H-mode plasmas started, and the beneficial effect of ICRF central electron heating to prevent W accumulation in the plasma core could be observed.

  13. IEEE TRANSACTIONS ON AUDIO, SPEECH, AND LANGUAGE PROCESSING, VOL. 20, NO. 6, AUGUST 2012 1869 Constrained Iterative Speech Enhancement

    E-Print Network [OSTI]

    Texas at Dallas, University of

    Constrained Iterative Speech Enhancement Using Phonetic Classes Amit Das, Student Member, IEEE, and John H. L enhancement algorithms like Auto-LSP, log-minimum mean squared error (log-MMSE), and log-MMSE with speech--Auditory masked threshold, Auto-LSP, con- strained iterative speech enhancement. I. INTRODUCTION NOISE is present

  14. DEVELOPMENT STATUS OF A SiC-FOAM BASED FLOW CHANNEL INSERT FOR A U.S.-ITER DCLL TBM

    E-Print Network [OSTI]

    Ghoniem, Nasr M.

    , CA, 91331, U.S.A. The U.S.-ITER DCLL (Dual Coolant Liquid Lead) TBM (Test Blanket Module) uses a Flow structure. I. INTRODUCTION The U.S. ITER Double Coolant Lead Lithium (DCLL) Test Blanket Module (TBM liquid breeder (PbLi) at elevated temperatures of more than 700 o C and at low velocities of ~10 cm

  15. Home / Privileged partnership with Japan to be explored on ITER: Privileged partnership with Japan to be explored on

    E-Print Network [OSTI]

    the negotiations between the six partners of ITER, the international thermonuclear reactor project, in the very and upgrading of supportive facilities to the ITER ­ reactor itself. Given the joint commitment to fusion energy should take into account a number of principles such as scientific autonomy, complementarity

  16. The effect of axial strain cycling on the critical current density and n-value of ITER niobium-tin

    E-Print Network [OSTI]

    Hampshire, Damian

    The effect of axial strain cycling on the critical current density and n-value of ITER niobium niobium-tin VAC and EM-LMI strands and the detailed characterisation of the EM-LMI-TFMC strand at -0 current density and n-value of two ITER candidate niobium-tin strands (EM- LMI and VAC). The strands were

  17. ITER: Japan to assign 20 percent of construction work to EU firms; Proposal for EU official to assume chief executive

    E-Print Network [OSTI]

    Experimental Reactor (ITER). Japan yesterday revealed the details of a proposal to host the project. Tokyo has, Japan bears half price even with construction inside the EU limits of the accessory structures prospect. The experimental device in order ITER generates electricity, reproducing the fusion reaction

  18. 5506 IEEE TRANSACTIONS ON SIGNAL PROCESSING, VOL. 55, NO. 11, NOVEMBER 2007 On the New Stopping Criteria of Iterative Turbo

    E-Print Network [OSTI]

    Hung, Shih-Hao

    Criteria of Iterative Turbo Decoding by Using Decoding Threshold Fan-Min Li and An-Yeu (Andy) Wu, Member--Decoding threshold, early termination (ET), extrinsic information transform (EXIT) chart, iterative decoding, turbo codes, turbo principle. I. INTRODUCTION IN 1993, a new class of forward-error-correction (FEC) code

  19. Factors Involved in Search Dog Training

    E-Print Network [OSTI]

    Alexander, Michael B.

    2010-07-14T23:59:59.000Z

    involved in training competent search dogs. Obedience training methods, age training was initiated, previous handler canine training experience, and handler perception and emotional attachment to their search dog were examined through a sixty-six question...

  20. COMMUNITY INVOLVEMENT PLAN APRIL 15, 1999.

    SciTech Connect (OSTI)

    GEIGER,K.

    1999-04-15T23:59:59.000Z

    This Community Involvement Plan has been prepared by the Brookhaven National Laboratory's Community Involvement Office with the input of the community, Laboratory employees and representatives of the U.S. Department of Energy. The process to develop the plan began with the formation of a focus group consisting of representatives from: the community at large; special interest groups within the community; the business community; Laboratory retirees; senior and line management from the Laboratory; and the U.S. Department of Energy. The focus group reviewed an initial outline developed by the Office of Community involvement, held in-depth roundtable discussions of community involvement needs, and created a draft plan based on their discussions. A workshop was held to present the draft Community Involvement Plan to a wider audience for their input and insights on how Brookhaven should involve the community in decision making. This workshop was advertised in local newspapers and within the Laboratory. It was attended by community members, special interest group representatives, Laboratory employees and managers, U.S. Department of Energy-Brookhaven Group management, and members of the Laboratory's Community Advisory Council. The results of the workshop discussions are incorporated in this plan.

  1. A Preliminary Analysis of Dose Rates Associated with ITER CVCS Equipment/Area Location

    SciTech Connect (OSTI)

    Blakeman, Edward D [ORNL; Ilas, Dan [ORNL; Petrov, Andrei Y [ORNL

    2012-03-01T23:59:59.000Z

    A preliminary analysis of the ITER Chemical and Volume Control System (CVCS) Area was performed to assess dose rates outside the walls and ceiling of the facility after 1.5 years of operation at shutdown, 2 days, and 10 days after shutdown. For this purpose a simplified Monte Carlo computer model was developed using the MCNP (MCNP5 Ver. 1.51) code. Two components are included: the smaller filter tank and the larger ion exchanger. These pieces of equipment are associated with the Integrated Blanket ELM Divertor Primary Heat Transfer System, which will have the largest dose rates associated with activated corrosion products during operation in comparison with other systems. The ion exchanger contained two source regions, a 1.2-m-thick resin bed above a 0.55 m-thick skirt, and a 0.8-m-thick water region. The filter constituted an additional source. Thus the model consisted of three sources (filter, resin, water), homogeneously distributed within the appropriate source regions. However, much of the results (that address individual isotopes) are presented with the two sources in the ion exchanger combined. In these cases the sources are referred to as the 'ion exchanger source' and the 'filter source.' Dimensions for the facility and components, as well as source isotopes and strengths, and material densities, were supplied by US ITER. Because of its simplification, the model does not contain pipes. Consequently, radiation streaming through pipe penetrations, radiation emanating from the pipes, and shielding from the pipes were not considered in this analysis. Dose rates on the outside of two walls and the ceiling were calculated. The two walls are labeled as the 'long' wall (aligned with the X-axis) and the 'short' wall (aligned with the Y-axis). These walls and ceiling were nominally set to 30-cm-thick concrete. In the original analysis, standard concrete (2.3 g/cc density) was used. In addition to the shielding walls/ceiling, a floor and an additional wall opposite the long wall were added for photon scattering contributions. These were both 10-cm-thick, standard concrete structures. Other components (tanks, pipes, etc.), that were not included in the model, would potentially add additional scattering and shielding. Possibly these additional effects will be addressed in a later, more detailed analysis. The room was 29.6 m in length (X-axis), but was limited to 15 m in the model. The inside width (Y axis) and height (Z axis) were 4 m and 3.4 m, respectively. The origin for the model was located inside the room at the corner opposite the long wall and adjacent to the short wall at the floor level. The room was filled with air at standard temperature and pressure. The stainless steel (SS304) wall thicknesses for the ion exchanger and filter were 2.2 cm and 0.8 cm, respectively. The axial center of the filter was located 140 cm from the short wall and 100 cm from the long wall (outer surface). The axial center of the ion exchanger was located 440 cm from the short wall and 250 cm from the long wall (inner surface). The resin was assumed to be a homogeneous mixture of equal atom density fractions of hydrogen and carbon* at a specified density of 1.136 g/cc. The filter material was assumed to be homogeneous carbon at a specified density of 1.8 g/cc. If the filter media were stainless steel and the accumulated activity were the same, the dose rate outside the filter would be lower, provided the density of the stainless steel sintered filter material is significantly higher than 1.8g/cc. The densities of the water and air were assumed to be 1.0 g/cc and 1.096E-3 g/cc, respectively. The model included 10 small volumes placed outside the model adjacent to the wall at locations where the dose rates were expected to be highest and which showed to a degree the fall-off of the dose rate with distance along a particular wall or ceiling. These 'tally cells' are shown in Fig. 2 and are described in Table 1. Each cell had dimensions of 50 cm x 50 cm x 1 cm and was oriented so that the 1-cm-thick dimension was perpendicular to the wall again

  2. Adopting iterative development: the perceived business Caryna Pinheiro, Frank Maurer, Jonathan Sillito

    E-Print Network [OSTI]

    Sillito, Jonathan

    processes that have been successfully implemented by others, to reduce the risk of failure [1]. The company under study is a large Oil & Gas government agency that lacked the initial management support to adopt an iterative development approach as well as the degree of formality and traceability desired by the top

  3. On the Logic of Iterated Belief Revision Adnan Darwiche and Judea Pearl

    E-Print Network [OSTI]

    California at Los Angeles, University of

    and inadequacies of the operator--based approach to belief revision [3, 4, 5, 13]. This paper addresses oneOn the Logic of Iterated Belief Revision Adnan Darwiche and Judea Pearl Cognitive Systems preservation of conditional beliefs during belief revision, thus permitting improper responses to sequences

  4. Fusion Power Associates Annual Meeting and Symposium Fusion Energy: Preparing for the NIF and ITER Era

    E-Print Network [OSTI]

    Materials Labs ­ S. Zinkle Fusion Technology ­ S. Milora 5:30 Depart ORNL 6:00 Reception 7:30 Board:50 Preparations for NIF Ignition Campaign ­ John Lindl, LLNL 9:10 Status of Z-Pinch Research ­ Keith Matzen Technology Program­ Stan Milora, ORNL 1:40 Issues and Opportunities from ITER Review ­ R. Hawryluk, PPPL 2

  5. Investigating the Impact of Changes in Iteration-likelihoods on Design Process Performance

    E-Print Network [OSTI]

    Shapiro, Daniel; Hamraz, Bahram; Sommer, Anita F.; Clarkson, P. John

    2015-01-01T23:59:59.000Z

    1 Investigating the Impact of Changes in Iteration-likelihoods on Design Process Performance Authors: Daniel Shapiro(1) (corresponding author, ds678@cam.ac.uk, +447922058809), Bahram Hamraz(2) (bh351@cam.ac.uk), Anita F. Sommer(1) (afs35@cam...

  6. U.S. PLANS AND STRATEGY FOR ITER BLANKET TESTING , M. Sawan4

    E-Print Network [OSTI]

    Abdou, Mohamed

    U.S. PLANS AND STRATEGY FOR ITER BLANKET TESTING M. Abdou1 , D. Sze2 , C. Wong3 , M. Sawan4 , A. Ying1 , N. B. Morley1 , S. Malang5 1 UCLA Fusion Engineering Sciences, Los Angeles, CA, abdou

  7. Synthesizing Representative I/O Workloads Using Iterative Distillation Zachary Kurmas

    E-Print Network [OSTI]

    Kurmas, Zachary

    Synthesizing Representative I/O Workloads Using Iterative Distillation Zachary Kurmas College proper- ties are "key" for a given workload and storage system. We have developed a tool, the Distiller, that automati- cally identifies the key properties ("attribute-values") of the workload. The Distiller then uses

  8. Generics, habituals, and iteratives Sentences may express information about particular events, such as

    E-Print Network [OSTI]

    Makous, Walter

    cough or flap (a wing)'. In English, John coughed can be understood as saying that he coughed once implications, especially those of intensity and/or prolongation. In English, John coughed and coughed is iterative in interpretation, like one understanding of the simple John coughed, but in addition implies

  9. A Generalized Iterative Water-filling Algorithm for Distributed Power Control in the Presence

    E-Print Network [OSTI]

    Luo, Zhi-Quan "Tom"

    1 A Generalized Iterative Water-filling Algorithm for Distributed Power Control in the Presence Engineering University of Minnesota, Minneapolis, MN 55455 Department of Industrial and Enterprise Systems and a jammer share a common spectrum of N orthogonal tones. Both the users and the jammer have limited power

  10. the Next Step for FE in China beyond ITER 10 -11 Dec.2013 Washington DC

    E-Print Network [OSTI]

    -sustained with TBR 1.2 Relay on existing ITER physicalk~1. 8-2, q > 3, H~1) and technical bases The goal of our design is to try to build the engineering testing reactor for fusion energy as early. CFETR will be one of the best test facility to develop the suitable materials for DEMO or FPP under

  11. High-Steady-State Advanced Tokamak Regimes for ITER and FIRE D. M. Meade1

    E-Print Network [OSTI]

    FT High- Steady-State Advanced Tokamak Regimes for ITER and FIRE D. M. Meade1 , N. R. Sauthoff1 , C Institute of Technology, Cambridge, MA 02139, USA An attractive tokamak-based fusion power plant will require the development of high- steady- state advanced tokamak regimes to produce a high gain burning

  12. Iterative-Expansion A* Colin M. Potts and Kurt D. Krebsbach

    E-Print Network [OSTI]

    Krebsbach, Kurt D.

    Iterative-Expansion A* (IEA*), fo- cuses on reducing redundant node expansions within indi- vidual depth IEA* with several other competing approaches. We also sketch proofs of optimality and com- pleteness for IEA*, and note that IEA* is particularly ef- ficient for solving implicitly-defined general graph

  13. BPO Inputs to ITER Design Review on Pellet Pacing, RMP and RWM Coils,

    E-Print Network [OSTI]

    BPO Inputs to ITER Design Review on Pellet Pacing, RMP and RWM Coils, and Disruption Mitigation Collaboration Essential Ingredient Contributions to Pellet Pacing USBPO: L. Baylor and P. Parks EU: P. Lang, A the acceptable energy loss from ELMs. Reducing the energy loss to pellet pacing is challenging. DIII

  14. Annual Report of the EURATOM/UKAEA Fusion Programme 2007/08 8 ITER Systems

    E-Print Network [OSTI]

    to measure the electron temperature and density profiles; · core charge exchange recombination spectroscopy (CXRS) to measure the helium (ash) content, the ion temperature and flow; · Ion Cyclotron Resonance of welding techniques for the ITER Vacuum Vessel. There has also been work by Durham University

  15. NATURE | Q&A Five-year delay would spell end of ITER

    E-Print Network [OSTI]

    States has high scientific and technological capability in fusion energy and has been one of the leading on Earth has long been a dream for physicists. In 2006, a team from the European Union, China, India, Japan of weight-loss Elizabeth Gibney Print #12;Related stories ITER keeps eye on prize Japan quake rocks fusion

  16. THE PATH TOWARD MAGNETIC FUSION ENERGY DEMONSTRATON AND THE ROLE OF ITER

    E-Print Network [OSTI]

    Abdou, Mohamed

    1 THE PATH TOWARD MAGNETIC FUSION ENERGY DEMONSTRATON AND THE ROLE OF ITER ABDOU, M. A. Center to enable a transition to fusion energy demonstration (DEMO). Fusion Nuclear Science and Technology (FNST conducting magnets. 1. Introduction: Fusion has great potential to be a sustainable energy source

  17. AN ITERATIVE SPATIO-TEMPORAL SPEECH ENHANCEMENT ALGORITHM FOR MICROPHONE ARRAYS

    E-Print Network [OSTI]

    Douglas, Scott C.

    AN ITERATIVE SPATIO-TEMPORAL SPEECH ENHANCEMENT ALGORITHM FOR MICROPHONE ARRAYS !"#"$ %&'t" "nd +c ABSTRACT We present a new spatio-temporal algorithm for speech enhancement using microphone arrays. Our-dependent parameter settings. Index Terms4 Speech enhancement, acoustic arrays, adaptive arrays, eigenvalues

  18. A completely iterative method for the infinite domain electrostatic problem with nonlinear dielectric media

    E-Print Network [OSTI]

    Dayal, Kaushik

    coupling a b s t r a c t We present an iterative method for the solution of the exterior all-space the device over all space, thus leading to an exterior electrostatic problem. In addition to this complexity in revised form 16 June 2011 Accepted 4 July 2011 Available online 20 July 2011 Keywords: Exterior

  19. On the Role of Update Constraints and TextTypes in Iterative Learning

    E-Print Network [OSTI]

    Stephan, Frank

    On the Role of Update Constraints and Text­Types in Iterative Learning Sanjay Jain 1,# , Timo learning considers therefore the usage of class­preserving one­one hypothesis spaces which limit this type of coding during the learning process. Other ways to limit it is to control the amount and types of updates

  20. June 28, 2005 U.S.Statements on International Fusion Reactor (ITER)

    E-Print Network [OSTI]

    June 28, 2005 U.S.Statements on International Fusion Reactor (ITER) Siting Decision WASHINGTON, DC fusion reactor will be located at the EU site in Cadarache, France. Below are statements by U for a robust management structure and an oversight program based on the principles of equity, accountability

  1. Europe and Japan with the elbow-with-elbow to accomodate engine ITER

    E-Print Network [OSTI]

    .12.03|13h1713h17 ? The competition for the machine installation of with thermonuclear fusion is announced, selected after a survey campaign, where the experimental engine with thermonuclear fusion ITER experts - thermonuclear fusion, who come to supra establish a new record in the engine with Tore fusion

  2. Thirty states sign ITER nuclear fusion plant deal 1 hour, 28 minutes ago

    E-Print Network [OSTI]

    Thirty states sign ITER nuclear fusion plant deal 1 hour, 28 minutes ago Representatives of more than 30 countries signed a deal on Tuesday to build the world's most advanced nuclear fusion reactor nuclear reactors, but critics argue it could be at least 50 years before a commercially viable reactor

  3. Praha 12/04/2007 Physics challenges and open issues of burning plasma physics in ITER

    E-Print Network [OSTI]

    Zonca, Fulvio

    of the fast ion source build-up: multi-scale approach Multi-mode simulations: so far mostly one or a few (AEs) (IV.2) Nonlinear physics of EP Modes (EPMs) (V) Long time scale behaviors and turbulence cross scale couplings (VI) ITER Applications (VII) Summary and Discussions #12;Praha 12/04/2007 Physics

  4. A Comparison of Iterative Methods for Least Squares Support Vector Machine Classi ers

    E-Print Network [OSTI]

    and Krylov methods (conjugate gradient, block-conjugate gra- dient). The latter show the best performance focus on two iter- ative algorithms: the successive overrelaxation method and the conjugate gradient steps, they are outperformed by the Krylov methods (conjugate gradient). Because, as will be shown later

  5. ITER UltraScaleScientific Joint Dark Energy Mission ComputingCapability

    E-Print Network [OSTI]

    #12;ITER UltraScaleScientific Joint Dark Energy Mission ComputingCapability Linac Coherent Light eRHIC Fusion Energy Contingency Source Upgrade HFIR Second Cold Source Integrated Beam Experiment IntroductionIntroductionIntroductionIntroductionIntroduction 8 Prioritization Process 9 A Benchmark

  6. Templates for the Solution of Linear Systems: Building Blocks for Iterative Methods 1

    E-Print Network [OSTI]

    Mignotte, Max

    Templates for the Solution of Linear Systems: Building Blocks for Iterative Methods 1 Richard of the Office of Energy Research, U.S. Department of Energy, under Contract DE­AC05­84OR21400, and the Stichting This book is also available in Postscript from over the Internet. To retrieve the postscript file you can

  7. MIMO PID Tuning via Iterated LMI Restriction S. Boyd M. Hast K. J. Astrom

    E-Print Network [OSTI]

    MIMO PID Tuning via Iterated LMI Restriction S. Boyd M. Hast K. J. °Astr¨om July 2, 2014 Abstract We formulate multi-input multi-output (MIMO) proportional-integral-derivative (PID) controller design, and provides a simple automated method for tuning MIMO PID controllers. The method is readily extended in many

  8. Solution characters of iterative coupling between energy simulation and CFD programs

    E-Print Network [OSTI]

    Chen, Qingyan "Yan"

    1 Solution characters of iterative coupling between energy simulation and CFD programs Zhiqiang Energy simulation (ES) and computational fluid dynamics (CFD) provide important and complementary information for building energy and indoor environment designs. A coupled ES and CFD simulation can eliminate

  9. Analyzing Social Network Structures in the Iterated Prisoner's Dilemma with Choice and Refusal

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    Analyzing Social Network Structures in the Iterated Prisoner's Dilemma with Choice and Refusal Mark structures emerge. We examine one particular IPD/CR environment and document the social network methods used within this environment. In particular, the social networks of interesting populations

  10. A Hybrid Iterative Solver for Robustly Capturing Coulomb Friction in Hair Dynamics

    E-Print Network [OSTI]

    A Hybrid Iterative Solver for Robustly Capturing Coulomb Friction in Hair Dynamics Gilles Daviet-slip instabilities. See the accompanying video for the full animations. Abstract Dry friction between hair fibers a hybrid strategy that combines a new zero-finding formulation of (exact) Coulomb friction together

  11. Solution characters of iterative coupling between energy simulation and CFD programs

    E-Print Network [OSTI]

    Zhai, John Z.

    States, building services consume more than one third of the primary energy consumption and twoSolution characters of iterative coupling between energy simulation and CFD programs Zhiqiang Zhaia Massachusetts Avenue, Cambridge, MA 02139-4307, USA b School of Mechanical Engineering, Purdue University, 1288

  12. PERTURBATION-BASED ERROR ANALYSIS OF ITERATIVE IMAGE RECONSTRUCTION ALGORITHM FOR X-RAY COMPUTED TOMOGRAPHY

    E-Print Network [OSTI]

    Fessler, Jeffrey A.

    -ray computed tomography. The effects of the quantization error in forward-projection, back computed tomography (CT) have been proposed to improve image quality and reduce dose [1]. These methodsPERTURBATION-BASED ERROR ANALYSIS OF ITERATIVE IMAGE RECONSTRUCTION ALGORITHM FOR X-RAY COMPUTED

  13. Iterative Spatial Sequence Estimator for Multi-Group Space Time Trellis Coded Systems

    E-Print Network [OSTI]

    Al-Ghadhban, Samir

    Iterative Spatial Sequence Estimator for Multi-Group Space Time Trellis Coded Systems Samir Al. The developed detector is called maximum a posteriori spatial sequence estimator and it has the flexibility. A novel spatial sequence estimator (SSE) for V-BLAST is proposed in [4]. The algorithm combines group

  14. Fuel Source Isotopic Tailoring Impact on ITER Design, Operation and Safety

    E-Print Network [OSTI]

    1 Fuel Source Isotopic Tailoring and Its Impact on ITER Design, Operation and Safety M. J. Gouge, W. The isotopic tailoring concept consists of utilizing a tritium-rich pellet source for core fueling and a deuterium- rich gas source for edge fueling. Because of the improved particle confinement associated

  15. ITERATIVE EXTRAPOLATION ALGORITHM FOR DATA RECONSTRUCTION OVER Wen Zhang, Rodney A. Kennedy and Thushara D. Abhayapala

    E-Print Network [OSTI]

    Abhayapala, Thushara D.

    ITERATIVE EXTRAPOLATION ALGORITHM FOR DATA RECONSTRUCTION OVER SPHERE Wen Zhang, Rodney A. Kennedy and Engineering The Australian National University Email: wen@cecs.anu.edu.au, rodney.kennedy@anu.edu.au, thushara, or colatitude and 0 360 is the azimuthal angle. The expansion of a function f L2 (S2 ) can be written as f

  16. Amesos2 and Belos: Direct and Iterative Solvers for Large Sparse Linear Systems

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Bavier, Eric; Hoemmen, Mark; Rajamanickam, Sivasankaran; Thornquist, Heidi

    2012-01-01T23:59:59.000Z

    Solvers for large sparse linear systems come in two categories: direct and iterative. Amesos2, a package in the Trilinos software project, provides direct methods, and Belos, another Trilinos package, provides iterative methods. Amesos2 offers a common interface to many different sparse matrix factorization codes, and can handle any implementation of sparse matrices and vectors, via an easy-to-extend C++ traits interface. It can also factor matrices whose entries have arbitrary “Scalar” type, enabling extended-precision and mixed-precision algorithms. Belos includes many different iterative methods for solving large sparse linear systems and least-squares problems. Unlike competing iterative solver libraries, Belos completely decouples themore »algorithms from the implementations of the underlying linear algebra objects. This lets Belos exploit the latest hardware without changes to the code. Belos favors algorithms that solve higher-level problems, such as multiple simultaneous linear systems and sequences of related linear systems, faster than standard algorithms. The package also supports extended-precision and mixed-precision algorithms. Together, Amesos2 and Belos form a complete suite of sparse linear solvers.« less

  17. Analysis of a Classification-based Policy Iteration Algorithm Alessandro Lazaric alessandro.lazaric@inria.fr

    E-Print Network [OSTI]

    be solved exactly and approximation techniques are required. In approximate policy iteration (API issues, mainly 3 and 4,1 variants of API have been proposed that replace the usual value function label. In this case, (x, a) for the rest of the actions are labeled negative and added to the training

  18. PUBLISHED VERSION Overview of LH experiments in JET with an ITER-like wall

    E-Print Network [OSTI]

    . The impact of these contributions on the performance of the auxiliary heating systems and the main achievements by these were reviewed in [2]. The main aspects of the operation of the Lower Hybrid (LH) system Republic Abstract: An overview of the recent results of Lower Hybrid (LH) experiments at JET with the ITER

  19. Theory needs for NSTX-U and ITER J. Menard, S. Kaye, and the

    E-Print Network [OSTI]

    Theory needs for NSTX-U and ITER J. Menard, S. Kaye, and the NSTX-U Topical Science Group Leaders PPPL Theory Department Retreat Princeton University and PPPL September 24-25 and 27, 2012 NSTX Wisconsin X Science LLC #12;NSTX-U PPPL Theory Department Retreat ­ September 24, 25, 27 2 Outline · NSTX

  20. Neil Calder -neil.calder@iter.org +33 6 14 16 41 75

    E-Print Network [OSTI]

    the quality of our environment." Further discussion of the schedule was held during the Cadarache meeting structure system or components have, by consultation with the Domestic Agencies and their industries. #12 that outline the progress on subjects such as: intellectual property management, the ITER Organization's budget

  1. Improved Confinement in JET High {beta} Plasmas with an ITER-Like Wall

    E-Print Network [OSTI]

    Challis, C D; Beurskens, M; Buratti, P; Delabie, E; Drewelow, P; Frassinetti, L; Giroud, C; Hawkes, N; Hobirk, J; Joffrin, E; Keeling, D; King, D B; Maggi, C F; Mailloux, J; Marchetto, C; McDonald, D; Nunes, I; Pucella, G; Saarelma, S; Simpson, J

    2015-01-01T23:59:59.000Z

    The replacement of the JET carbon wall (C-wall) by a Be/W ITER-like wall (ILW) has affected the plasma energy confinement. To investigate this, experiments have been performed with both the C-wall and ILW to vary the heating power over a wide range for plasmas with different shapes.

  2. Test Strategy for the European HCPB Test Blanket Module in ITER

    SciTech Connect (OSTI)

    Boccaccini, L.V.; Meyder, R.; Fischer, U. [Forschungszentrum Karlsruhe (Germany)

    2005-05-15T23:59:59.000Z

    According to the European Blanket Programme two blanket concepts, the Helium Cooled Pebble Bed (HCPB) and a Helium Cooled Lithium Lead (HCLL) will be tested in ITER. During 2004 the test blanket modules (TBM) of both concepts were redesigned with the goal to use as much as possible similar design options and fabrication techniques for both types in order to reduce the European effort for TBM development. The result is a robust TBM box being able to withstand 8 MPa internal pressure in case of in-box LOCA; the TBM box consists of First wall (FW), caps, stiffening grid and manifolds. The box is filled with typically 18 and 24 breeding units (BU), for HCPB and HCLL respectively. A breeding unit has about 200 mm in poloidal and toroidal direction and about 400 mm in radial direction; the design is adapted to contain and cooling ceramic breeder/beryllium pebble beds for the HCPB and eutectic Lithium-Lead for the HCLL.The use of a new material, EUROFER, and the innovative design of these Helium Cooled components call for a large qualification programme before the installation in ITER; availability and safety of ITER should not be jeopardised by a failure of these components. Fabrication technologies especially in the welding processes (diffusion welding, EB, TIG, LASER) need to be tested in the manufacturing of large mock-ups; an extensive out-of-pile programme in Helium facility should be foreseen for the verification of the concept from basic helium cooling functions (uniformity of flow in parallel channels, heat transfer coefficient in FW, etc.) up to the verification of large portions of the TBM design under relevant ITER loading.In ITER the TBM will have the main objective to collect information that will contribute to the final design of DEMO blankets. A strategy has been proposed in 2001 that leads to the tests in ITER 4 different Test Blanket Modules (TBM's) type during the first 10 years of ITER operation. For the new HCPB design this strategy is confirmed with some additional possibilities taking into account the modular design of the breeding zone.

  3. The Japan Times Printer Friendly Articles France has won the competition to host the International Thermonuclear Experimental Reactor (ITER), the world's first nuclear-

    E-Print Network [OSTI]

    the International Thermonuclear Experimental Reactor (ITER), the world's first nuclear- fusion reactor. Japan fought wins by withdrawing ITER bid Thermonuclear fusion utilizes the same process that powers the sun -- nuclear-fusion reactions -- to produce energy. Scientists at the ITER plant will create nuclear-fusion

  4. Slide 1/14Fusion Power Associate Washington DC 10-11 December 2013OM13897 Status Report of the ITER Project

    E-Print Network [OSTI]

    as an independent international organization ­ Develop a process where objectives and strategy defined by the DG-General of the ITER Organization Aerial view of ITER Site in September 2013 (F4E) #12;Slide 2/14Fusion Power Associate more power than it receives; · The ITER Project creates a new collaborative culture and standard

  5. Twin-Screw Extruder Development for the ITER Pellet Injection System

    SciTech Connect (OSTI)

    Meitner, Steven J [ORNL; Baylor, Larry R [ORNL; Combs, Stephen Kirk [ORNL; Fehling, Dan T [ORNL; McGill, James M [ORNL; Rasmussen, David A [ORNL; Leachman, J. W. [University of Wisconsin, Madison

    2009-01-01T23:59:59.000Z

    The ITER pellet injection system is comprised of devices to form and accelerate pellets, and will be connected to inner wall guide tubes for fueling, and outer wall guide tubes for ELM pacing. An extruder will provide a stream of solid hydrogen isotopes to a secondary section, where pellets are cut and accelerated with a gas gun into the plasma. The ITER pellet injection system is required to provide a plasma fueling rate of 120 Pa-m3/s (900 mbar-L/s) and durations of up to 3000 s. The fueling pellets will be injected at a rate up to 10 Hz and pellets used to trigger ELMs will be injected at higher rates up to 20 Hz. A twin-screw extruder for the ITER pellet injection system is under development at the Oak Ridge National Laboratory. A one-fifth ITER scale prototype has been built and has demonstrated the production of a continuous solid deuterium extrusion. The 27 mm diameter, intermeshed, counter-rotating extruder screws are rotated at a rate up to ?5 rpm. Deuterium gas is pre-cooled and liquefied and solidified in separate extruder barrels. The precooler consists of a deuterium gas filled copper coil suspended in a separate stainless steel vessel containing liquid nitrogen. The liquefier is comprised of a copper barrel connected to a Cryomech AL330 cryocooler, which has a machined helical groove surrounded by a copper jacket, through which the pre-cooled deuterium condenses. The lower extruder barrel is connected to a Cryomech GB-37 cryocooler to solidify the deuterium (at ?15 K) before it is forced through the extruder die. The die forms the extrusion to a 3 mm x 4 mm rectangular cross section. Design improvements have been made to improve the pre-cooler and liquefier heat exchangers, to limit the loss of extrusion through gaps in the screws. This paper will describe the design improvements for the next iteration of the extruder prototype.

  6. Physical Models of Noncovalent Interactions Involving Aromatic Rings

    E-Print Network [OSTI]

    Bloom, Jacob Walter Goldstein

    2014-04-17T23:59:59.000Z

    of the interaction energies for sandwich dimers of Bz-X…Tz(N) versus Bz-X…Tz(C), at R = 4.0 Å. ............................................................................................................. 63 Figure 4.8: Electrostatic potential (solid colors, kcal...) for sandwich dimers of (a) Bz-X…Tz(C) versus Bz-X…Tz(N) and (b) Bz-X…Bz versus Bn(N)-X…Bz. ................................................................................................ 58 Figure 4.6: (a) Relative SAPT0 interaction energies (R = Re) and (b...

  7. Iterative gradient descent approach to multiple regression with fuzzy data

    E-Print Network [OSTI]

    Bargiela, Andrzej

    to multiple regression and lay foundation for a further generalisation to multiple non-linear regression dictates adoption of a more general viewpoint, regression variables are given as non-numerical entities of the parameters of the regression model have been derived only for the case of a simple linear regression, i

  8. Beyond ITER: RF Heating and Current Drive Issues for DEMO

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    control systems for profile control? · Can we inject adequate power with available ports? · Will real control Need to operate reliably in a high power flux, high radiation, and "steady state" nuclear · Existing models unable to predict how much power can be coupled into core from a given launcher ­ Currently

  9. An iterative technique for the factorization of polynomials

    E-Print Network [OSTI]

    Gray, Jerry Edwin

    1964-01-01T23:59:59.000Z

    = Z pb, 0&) &m-1 i n-)-1' Then, (2. 4) f(z) = g(z) h (z) m-1 + i=o i rz For the procf construct the right l. and side of (2. 4), m-1 g(z) h(z) + i=o rz = S pz p bz m-1 + k=o k rkz E k=o E i+j =k i&m ]& n-m n-k pb z m-1 + E r z...-1 + g, '=o Thus we may write for the right hand side of (2. 4) (2. 5) n-m min [k, m] 7 k=o i=o 0& k-i~ n-m n-k Pik i' n + km-m+1 min [k, n-m] E ]=0 0&k-] & m n-k p b z k-] E k =n-m+1 n-k I Z n-k n-m for the part involving E...

  10. Compact, Convex Upper Bound Iteration for Approximate POMDP Planning

    E-Print Network [OSTI]

    Wang, Tao

    uncertainty How to act based on past experience Maximize long term reward Wide range of applications Robotics and autonomous agent design Helicopter control, Robot navigation and mapping Nursing , Elderly assistance Others #12;POMDP model s0 s0 a1 a1 o1 o1 s1 s1 s2 s2 a2 a2 o2 o2 st st at at ot ot r0 r0 r1 r1 r2 r2 rt rt

  11. A new iterative approach to solving the transport equation

    E-Print Network [OSTI]

    Maslowski Olivares, Alexander Enrique

    2009-05-15T23:59:59.000Z

    and Dr. Ed Larsen for their insightful discussions on slab geometry Caseology and its extension to multiple dimensions. The final stage of this research was completed at Lawrence Livermore National Laboratory. I thank Dr. Patrick Brantley and AX... arrowrightnosp . Although this model has few physical applications in itself, it is consistent with the transport equation for a single group belonging to the multi-group discretization (Lewis and Miller.) Thus, an algorithm that is scalable in space an angle...

  12. Comparisons of Predicted Plasma Performance in ITER H-mode Plasmas with Various Mixes of External He

    SciTech Connect (OSTI)

    R.V. Budny

    2009-03-20T23:59:59.000Z

    Performance in H-mode DT plasmas in ITER with various choices of heating systems are predicted and compared. Combinations of external heating by Negative Ion Neutral Beam Injection (NNBI), Ion Cyclotron Range of Frequencies (ICRF), and Electron Cyclotron Heating (ECH) are assumed. Scans with a range of physics assumptions about boundary temperatures in the edge pedestal, alpha ash transport, and toroidal momentum transport are used to indicate effects of uncertainties. Time-dependent integrated modeling with the PTRANSP code is used to predict profiles of heating, beam torque, and plasma profiles. The GLF23 model is used to predict temperature profiles. Either GLF23 or the assumption of a constant ratio for ?ø/?i is used to predict toroidal rotation profiles driven by the beam torques. Large differences for the core temperatures are predicted with different mixes of the external heating during the density and current ramp-up phase, but the profiles are similar during the flattop phase. With ?ø/?i = 0.5, the predicted toroidal rotation is relatively slow and the flow shear implied by the pressure, toroidal rotation, and neoclassical poloidal rotation are not sufficient to cause significant changes in the energy transport or steady state temperature profiles. The GLF23-predicted toroidal rotation is faster by a factor of six, and significant flow shear effects are predicted.

  13. Environmental science and ecology involve studies

    E-Print Network [OSTI]

    Christensen, Dan

    Environmental science and ecology involve studies of the biosphere, hydro- sphere, and lithosphere in environmental science is conducted on spatial scales varying from a single algal cell to the Earth as a whole's environmental scientists require investigation by an interdisciplinary team, including members from several

  14. Increasing Public Involvement in Structural Biology

    E-Print Network [OSTI]

    Baker, David

    --often referred to as citizen science--provides a means of engaging people's skills, rather than just for the public to get actively involved in structural biology research? Citizen science projects can require areas for citizen science as structural problems both are amenable to human spatial-reasoning skills

  15. Ion cyclotron resonance frequency heating in JET during initial operations with the ITER-like wall

    SciTech Connect (OSTI)

    Jacquet, P., E-mail: philippe.jacquet@ccfe.ac.uk; Monakhov, I.; Arnoux, G.; Brix, M.; Graham, M.; Meigs, A.; Sirinelli, A. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Bobkov, V.; Devaux, S.; Drewelow, P.; Pütterich, T. [Max-Planck-Institut für Plasmaphysik, EURATOM-Assoziation, Garching (Germany); Colas, L. [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Czarnecka, A. [Association Euratom-IPPLM, Hery 23, 01-497 Warsaw (Poland); Lerche, E.; Van-Eester, D. [Association EURATOM-Belgian State, ERM-KMS, Brussels (Belgium); Mayoral, M.-L. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); EFDA Close Support Unit, Garching (Germany); Brezinsek, S. [IEK-4, Forschungszentrum Jülich, Association EURATOM-FZJ, Jülich (Germany); Campergue, A.-L. [Ecole Nationale des Ponts et Chaussées, F77455 Marne-la-Vallée (France); Klepper, C. C. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6169 (United States); Milanesio, D. [Politecnico di Torino, Department of Electronics, Torino (Italy); and others

    2014-06-15T23:59:59.000Z

    In 2011/12, JET started operation with its new ITER-Like Wall (ILW) made of a tungsten (W) divertor and a beryllium (Be) main chamber wall. The impact of the new wall materials on the JET Ion Cyclotron Resonance Frequency (ICRF) operation is assessed and some important properties of JET plasmas heated with ICRF are highlighted. A???20% reduction of the antenna coupling resistance is observed with the ILW as compared with the JET carbon (JET-C) wall. Heat-fluxes on the protecting limiters close the antennas, quantified using Infra-Red thermography (maximum 4.5?MW/m{sup 2} in current drive phasing), are within the wall power load handling capabilities. A simple RF sheath rectification model using the antenna near-fields calculated with the TOPICA code can reproduce the heat-flux pattern around the antennas. ICRF heating results in larger tungsten and nickel (Ni) contents in the plasma and in a larger core radiation when compared to Neutral Beam Injection (NBI) heating. The location of the tungsten ICRF specific source could not be identified but some experimental observations indicate that main-chamber W components could be an important impurity source: for example, the divertor W influx deduced from spectroscopy is comparable when using RF or NBI at same power and comparable divertor conditions, and Be evaporation in the main chamber results in a strong reduction of the impurity level. In L-mode plasmas, the ICRF specific high-Z impurity content decreased when operating at higher plasma density and when increasing the hydrogen concentration from 5% to 15%. Despite the higher plasma bulk radiation, ICRF exhibited overall good plasma heating performance; the power is typically deposited at the plasma centre while the radiation is mainly from the outer part of the plasma bulk. Application of ICRF heating in H-mode plasmas has started, and the beneficial effect of ICRF central electron heating to prevent W accumulation in the plasma core has been observed.

  16. k-line iterative methods: a conjugate-gradient approach

    SciTech Connect (OSTI)

    Kratzer, D.; Parter, S.V.; Steuerwalt, M.

    1981-03-29T23:59:59.000Z

    The generalized conjugate gradient scheme based on the k-line block Jacobi splitting A = M-N was studied for solving model two-dimensional parabolic and elliptic difference equations AU = F tilde. A represents the matrix ch/sup ..cap alpha../-h/sup 2/..delta../sub h/. Eigenvalues of M/sup -1/N cluster, and the cluster radii decrease as ch/sup ..cap alpha../ or k increases. Computations with k = 4, 8, 16, 32, and ch/sup ..cap alpha../ = 0, h, 2 are discussed.

  17. Experimental neutronics tests for a neutron activation system for the European ITER TBM

    SciTech Connect (OSTI)

    Klix, A.; Fischer, U. [Karlsruhe Institute of Technology (KIT), INR, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Gehre, D. [Technical University of Dresden, IKTP, Zellescher Weg 19, 01062 Dresden (Germany); Kleizer, G. [Karlsruhe Institute of Technology (KIT), INR, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany and Budapest University of Technology and Economics, M?egyetem rkp. 3-9. H-1111 Budapest (Hungary); Raj, P. [Karlsruhe Institute of Technology (KIT), INR, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany and Université Paris-Sud, 15 rue Georges Clemenceau, F-91405 Paris (France); Rovni, I. [Budapest University of Technology and Economics, M?egyetem rkp. 3-9. H-1111 Budapest (Hungary); Ruecker, Tom [Karlsruhe Institute of Technology (KIT), INR, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany and University of Applied Sciences Zittau-Goerlitz, Theodor-Körner-Allee 16, D-02754 Zittau (Germany)

    2014-08-21T23:59:59.000Z

    We are investigating methods for neutron flux measurement in the ITER TBM. In particular we have tested sets of activation materials leading to induced gamma activities with short half-lives of the order of tens of seconds up to minutes and standard activation materials. Packages of activation foils have been irradiated with the intense neutron generator of Technical University of Dresden in a pure DT neutron field as well as in a neutronics mock-up of the European ITER HCLL TBM. An important aim was to check whether the gamma activity induced in the activation foils in these packages could be measured simultaneously. It was indeed possible to identify gamma lines of interest in gamma-ray measurements immediately after extraction from the irradiation.

  18. Tritium processing system for the ITER Li/V blanket test module

    SciTech Connect (OSTI)

    Sze, D.K.; Hua, T.Q. [Argonne National Lab., IL (United States); Abdou, M.A. [Univ. of California, Los Angeles, CA (United States); Dagher, M.A.; Waganer, L.M.

    1997-04-01T23:59:59.000Z

    The purpose of the ITER Blanket Testing Module is to test the operating and performance of candidate blanket concepts under a real fusion environment. To assure fuel self-sufficiency the tritium breeding, recovery and processing have to be demonstrated. The tritium produced in the blanket has to be processed to a purity which can be used for refueling. All these functions need to be accomplished so that the tritium system can be scaled to a commercial fusion power plant from a safety and reliability point of view. This paper summarizes the tritium processing steps, the size of the equipment, power requirements, space requirements, etc. for a self-cooled lithium blanket. This information is needed for the design and layout of the test blanket ancillary system and to assure that the ITER guidelines for remote handling of ancillary equipment can be met.

  19. Clover Action for Blue Gene-Q and Iterative solvers for DWF

    E-Print Network [OSTI]

    Karthee Sivalingam; Peter Boyle

    2014-08-28T23:59:59.000Z

    In Lattice QCD, a major challenge in simulating physical quarks is the computational complexity of these simulations. In this proceeding, we describe the optimisation of Clover fermion action for Blue gene-Q architecture and how different iterative solvers behave for Domain Wall Fermion action. We find that the optimised Clover term achieved a maximum efficiency of 29.1% and 20.2% for single and double precision respectively for iterative Conjugate Gradient solver. For Domain Wall Fermion action (DWF) we found that Modified Conjugate Residual(MCR) as the most efficient solver compared to CG and GCR. We have developed a new multi-shift MCR algorithm that is 18.5% faster compared to multi-shift CG for the evaluation of rational functions in RHMC.

  20. Design and Overview of 100 kV Bushing for the DNB Injector of ITER

    SciTech Connect (OSTI)

    Shah, Sejal; Bandyopadhyay, M.; Rotti, C.; Singh, M. J.; Roopesh, G.; Chakraborty, A. K. [ITER-India, Institute for Plasma Research, Gandhinagar-382025, Gujarat (India); Rajesh, S. [ITER-India, Institute for Plasma Research, Gandhinagar-382025, Gujarat (India); Microelectronics and Materials Physics Labs, P.O.Box 4500, FIN-90014 University of Oulu (Finland); Nishad, S.; Srusti, B. [DesignTech Systems Ltd, Banjara Hills, Hyderabad, Andhra Pradesh-500034 (India); Schunke, B.; Hemsworth, R.; Chareyre, J.; Svensson, L. [ITER Organisation, Route de Vinon, CS 90 046, 13067 St. Paul lez Durance Cedex (France)

    2011-09-26T23:59:59.000Z

    The 100 kV bushing is one of the most important and technologically challenging Safety Important Class (SIC) components of the Diagnostic Neutral Beam (DNB) injector of ITER. It forms interface between gas insulated electrical transmission line and torus primary vacuum and acts as a vacuum feedthrough of ITER. Design optimization has been carried out to meet the electric and structural requirements based on its classification. Unlike HNB bushing, single stage bushing is designed to provide 100 kV isolation. Finite Element Analysis (FEA) based optimization has been carried out for electrostatic and structural analysis. Manufacturing assembly sequence is studied and presented in this paper. However validation of the same is foreseen from manufacturer.

  1. Assessment of database for interaction of tritium with ITER plasma facing materials

    SciTech Connect (OSTI)

    Dolan, T.J.; Anderl, R.A.

    1994-09-01T23:59:59.000Z

    The present work surveys recent literature on hydrogen isotope interactions with Be, SS and Inconels, Cu, C, and V, and alloys of Cu and V. The goals are (1) to provide input to the International Thermonuclear Experimental Reactor (ITER) team to help with tritium source term estimates for the Early Safety and Environmental Characterization Study and (2) to provide guidance for planning additional research that will be needed to fill gaps in the present materials database. Properties of diffusivity, solubility, permeability, chemical reactions, Soret effect, recombination coefficient, surface effects, trapping, porosity, layered structures, interfaces, and oxides are considered. Various materials data are tabulated, and a matrix display shows an assessment of the quality of the data available for each main property of each material. Recommendations are made for interim values of diffusivity and solubility to be used, pending further discussion by the ITER community.

  2. Suppression of Tritium Retention in Remote Areas of ITER by Nonperturbative Reactive Gas Injection

    SciTech Connect (OSTI)

    Tabares, F. L.; Ferreira, J. A.; Ramos, A. [As Euratom-Ciemat, Av Complutense 22, 28040 Madrid (Spain); Rooij, G. van; Westerhout, J.; Al, R.; Rapp, J. [FOM Instituut voor Plasmafysica Rijnhuizen, EURATOM Association, TEC, PO Box 1207, 3430 BE Nieuwegein (Netherlands); Drenik, A.; Mozetic, M. [As Euratom-MHEST, Institut Jozef Stefan, Jamova cesta 39, 1000 Ljubljana (Slovenia)

    2010-10-22T23:59:59.000Z

    A technique based on reactive gas injection in the afterglow region of the divertor plasma is proposed for the suppression of tritium-carbon codeposits in remote areas of ITER when operated with carbon-based divertor targets. Experiments in a divertor simulator plasma device indicate that a 4 nm/min deposition can be suppressed by addition of 1 Pa{center_dot}m{sup 3} s{sup -1} ammonia flow at 10 cm from the plasma. These results bolster the concept of nonperturbative scavenger injection for tritium inventory control in carbon-based fusion plasma devices, thus paving the way for ITER operation in the active phase under a carbon-dominated, plasma facing component background.

  3. Vacuum Bellows, Vacuum Piping, Cryogenic Break, and Copper Joint Failure Rate Estimates for ITER Design Use

    SciTech Connect (OSTI)

    L. C. Cadwallader

    2010-06-01T23:59:59.000Z

    The ITER international project design teams are working to produce an engineering design in preparation for construction of the International Thermonuclear Experimental Reactor (ITER) tokamak. During the course of this work, questions have arisen in regard to safety barriers and equipment reliability as important facets of system design. The vacuum system designers have asked several questions about the reliability of vacuum bellows and vacuum piping. The vessel design team has asked about the reliability of electrical breaks and copper-copper joints used in cryogenic piping. Research into operating experiences of similar equipment has been performed to determine representative failure rates for these components. The following chapters give the research results and the findings for vacuum system bellows, power plant stainless steel piping (amended to represent vacuum system piping), cryogenic system electrical insulating breaks, and copper joints.

  4. Neutronics and thermal design analyses of US solid breeder blanket for ITER

    SciTech Connect (OSTI)

    Gohar, Y.; Billone, M.; Attaya, H. (Argonne National Lab., IL (USA)); Sawan, M. (Wisconsin Univ., Madison, WI (USA))

    1990-09-01T23:59:59.000Z

    The US Solid Breeder Blanket is designed to produce the necessary tritium required for the ITER operation and to operate at power reactor conditions as much as possible. Safety, low tritium inventory, reliability, flexibility cost, and minimum R D requirements are the other design criteria. To satisfy these criteria, the produced tritium is recovered continuously during operation and the blanket coolant operates at low pressure. Beryllium multiplier material is used to control the solid-breeder temperature. Neutronics and thermal design analyses were performed in an integrated manner to define the blanket configuration. The reference parameters of ITER including the operating scenarios, the neutron wall loading distribution and the copper stabilizer are included in the design analyses. Several analyses were performed to study the impact of the reactor parameters, blanket dimensions, material characteristics, and heat transfer coefficient at the material interfaces on the blanket performance. The design analyses and the results from the different studies are summarized. 6 refs., 3 figs., 3 tabs.

  5. US ITER (International Thermonuclear Experimental Reactor) shield and blanket design activities

    SciTech Connect (OSTI)

    Baker, C.C.

    1988-08-01T23:59:59.000Z

    This paper summarizes nuclear-related work in support of the US effort for the International Thermonuclear Experimental Reactor (ITER) Study. Primary tasks carried out during the past year include design improvements of the inboard shield developed for the TIBER concept, scoping studies of a variety of tritium breeding blanket options, development of necessary design guidelines and evaluation criteria for the blanket options, further safety considerations related to nuclear components, and issues regarding structural materials for an ITER device. The blanket concepts considered are the aqueous/Li salt solution, a water-cooled, solid breeder blanket, a helium-cooled, solid-breeder blanket, a blanket cooled by helium containing lithium-bearing particulates, and a blanket concept based on breeding tritium from He/sup 3/. 1 ref., 2 tabs.

  6. Review of the International Thermonuclear Experimental Reactor (ITER) detailed design report

    SciTech Connect (OSTI)

    NONE

    1997-04-18T23:59:59.000Z

    Dr. Martha Krebs, Director, Office of Energy Research at the US Department of Energy (DOE), wrote to the Fusion Energy Sciences Advisory Committee (FESAC), in letters dated September 23 and November 6, 1996, requesting that FESAC review the International Thermonuclear Experimental Reactor (ITER) Detailed Design Report (DDR) and provide its view of the adequacy of the DDR as part of the basis for the United States decision to enter negotiations with the other interested Parties regarding the terms and conditions for an agreement for the construction, operations, exploitation and decommissioning of ITER. The letter from Dr. Krebs, referred to as the Charge Letter, provided context for the review and a set of questions of specific interest.

  7. In-Vessel Coil Material Failure Rate Estimates for ITER Design Use

    SciTech Connect (OSTI)

    L. C. Cadwallader

    2013-01-01T23:59:59.000Z

    The ITER international project design teams are working to produce an engineering design for construction of this large tokamak fusion experiment. One of the design issues is ensuring proper control of the fusion plasma. In-vessel magnet coils may be needed for plasma control, especially the control of edge localized modes (ELMs) and plasma vertical stabilization (VS). These coils will be lifetime components that reside inside the ITER vacuum vessel behind the blanket modules. As such, their reliability is an important design issue since access will be time consuming if any type of repair were necessary. The following chapters give the research results and estimates of failure rates for the coil conductor and jacket materials to be used for the in-vessel coils. Copper and CuCrZr conductors, and stainless steel and Inconel jackets are examined.

  8. Nonlinear Projective-Iteration Methods for Solving Transport Problems on Regular and Unstructured Grids

    SciTech Connect (OSTI)

    Dmitriy Y. Anistratov; Adrian Constantinescu; Loren Roberts; William Wieselquist

    2007-04-30T23:59:59.000Z

    This is a project in the field of fundamental research on numerical methods for solving the particle transport equation. Numerous practical problems require to use unstructured meshes, for example, detailed nuclear reactor assembly-level calculations, large-scale reactor core calculations, radiative hydrodynamics problems, where the mesh is determined by hydrodynamic processes, and well-logging problems in which the media structure has very complicated geometry. Currently this is an area of very active research in numerical transport theory. main issues in developing numerical methods for solving the transport equation are the accuracy of the numerical solution and effectiveness of iteration procedure. The problem in case of unstructured grids is that it is very difficult to derive an iteration algorithm that will be unconditionally stable.

  9. The ITER pre-compression rings – A first in cryogenic composite technology

    SciTech Connect (OSTI)

    Rajainmaki, Hannu; Fanthome, John; Losasso, Marcello [Fusion for Energy, C/ Josep Pla, n. 2, E-08019 Barcelona (Spain); Foussat, Arnaud [ITER Organisation, 13108 St. Paul-lez-Durance (France); Rodriguez, Jesus [EADS CASA Espacio S.L., Av. de Aragón 404, E-28022 Madrid (Spain); Evans, David; Diaz, Victor [Advanced Cryogenic Materials Ltd, Abingdon, OX14 2HQ (United Kingdom)

    2014-01-27T23:59:59.000Z

    The ITER Pre-Compression Rings represent one of the heaviest composite structures ever manufactured as a single piece and the largest - the outer diameter will be above 5.5 meters - intended for use in a cryogenic environment. With a cross section of 337 mm × 288 mm, each item will weigh more than 3,000 kg. A development program, based on filament wound and dry wound S2 glass unidirectional fibers, the latter processed by VARTM, was completed on one fifth scale rings, and these materials and techniques were shown to be satisfactory. The paper describes how a technology applied to build up primary structures of European launchers is being accommodated to produce the ITER Pre-Compression Rings, fulfilling its extremely challenging requirements. In addition, we will describe how the structural analysis is correlated with the test results of scaled down rings, as well as how the pre-compression rings’ manufacturing process will be qualified.

  10. Hybrid preconditioning for iterative diagonalization of ill-conditioned generalized eigenvalue problems in electronic structure calculations

    SciTech Connect (OSTI)

    Cai, Yunfeng, E-mail: yfcai@math.pku.edu.cn [LMAM and School of Mathematical Sciences, Peking University, Beijing 100871 (China) [LMAM and School of Mathematical Sciences, Peking University, Beijing 100871 (China); Department of Computer Science, University of California, Davis 95616 (United States); Bai, Zhaojun, E-mail: bai@cs.ucdavis.edu [Department of Computer Science and Department of Mathematics, University of California, Davis 95616 (United States)] [Department of Computer Science and Department of Mathematics, University of California, Davis 95616 (United States); Pask, John E., E-mail: pask1@llnl.gov [Condensed Matter and Materials Division, Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Sukumar, N., E-mail: nsukumar@ucdavis.edu [Department of Civil and Environmental Engineering, University of California, Davis 95616 (United States)

    2013-12-15T23:59:59.000Z

    The iterative diagonalization of a sequence of large ill-conditioned generalized eigenvalue problems is a computational bottleneck in quantum mechanical methods employing a nonorthogonal basis for ab initio electronic structure calculations. We propose a hybrid preconditioning scheme to effectively combine global and locally accelerated preconditioners for rapid iterative diagonalization of such eigenvalue problems. In partition-of-unity finite-element (PUFE) pseudopotential density-functional calculations, employing a nonorthogonal basis, we show that the hybrid preconditioned block steepest descent method is a cost-effective eigensolver, outperforming current state-of-the-art global preconditioning schemes, and comparably efficient for the ill-conditioned generalized eigenvalue problems produced by PUFE as the locally optimal block preconditioned conjugate-gradient method for the well-conditioned standard eigenvalue problems produced by planewave methods.

  11. Current Control in ITER Steady State Plasmas With Neutral Beam Steering

    SciTech Connect (OSTI)

    R.V. Budny

    2009-09-10T23:59:59.000Z

    Predictions of quasi steady state DT plasmas in ITER are generated using the PTRANSP code. The plasma temperatures, densities, boundary shape, and total current (9 - 10 MA) anticipated for ITER steady state plasmas are specified. Current drive by negative ion neutral beam injection, lower-hybrid, and electron cyclotron resonance are calculated. Four modes of operation with different combinations of current drive are studied. For each mode, scans with the NNBI aimed at differing heights in the plasma are performed to study effects of current control on the q profile. The timeevolution of the currents and q are calculated to evaluate long duration transients. Quasi steady state, strongly reversed q profiles are predicted for some beam injection angles if the current drive and bootstrap currents are sufficiently large.

  12. Undergraduate business and management students’ experiences of being involved in assessment 

    E-Print Network [OSTI]

    Tai, Chunming

    2012-11-29T23:59:59.000Z

    This study aimed to explore university undergraduates’ experiences of student involvement in assessment (SIA). Based on Biggs’ 3P model of student learning, this study focused on students’ experiences prior to SIA, during ...

  13. Studies on Pellet Fueling of ITER-Like Plasmas

    SciTech Connect (OSTI)

    Kamelander, Gerald [Austrian Research Center Seibersdorf (Austria); Weimann, Geert [Austrian Research Center Seibersdorf (Austria); Garzotti, Luca [Consorzio RFX, Corso Stati Uniti 4 (Italy); Litaudon, Xavier [DSM, CEA Cadarache (France); Moreau, Didier [DSM, CEA Cadarache (France); Pegourie, Bernard [DSM, CEA Cadarache (France)

    2004-06-15T23:59:59.000Z

    The paper reports on simulation of pellet-fueled plasmas in a fusion reactor. The simulations have been performed by means of the ASTRA transport code. We have studied physical modeling of pellet injection as well as the numerical conditions to resolve pellet injection correctly. As a first step the essential mechanisms for density control have been studied based on simplified assumptions with a generic source of additional heating. The experience gained has been used to simulate advanced scenarios including internal transport barriers. It has been confirmed that it is possible to drive the plasma of a next-generation tokamak into a high-Q regime and to maintain it in a steady-state regime. Nevertheless, the pellet injection parameters required are rather demanding and imply a significant technological improvement of pellet injectors. Those investigations represent an improvement of simulations done earlier with a control of the central density at constant profile.

  14. Spain offers a total of 900 Millions Spain proposes to double her contribution to host ITER, the experimental fusion

    E-Print Network [OSTI]

    that the government expects the European Union take into account this Spanish financial commitment in the final ITER site between France, with the Cadarache site, and Spain with Vandellos. The Spanish government has

  15. Detailed search US supports Japanese bid to host ITER as France urges Europe to go it alone

    E-Print Network [OSTI]

    support of his country for the Japanese bid to host the international thermonuclear site (ITER thermonuclear site if the French candidate is not selected for the international project. However

  16. Report of a technical evaluation panel on the use of beryllium for ITER plasma facing material and blanket breeder material

    SciTech Connect (OSTI)

    Ulrickson, M.A. [ed.] [Sandia National Labs., Albuquerque, NM (United States); Manly, W.D. [Oak Ridge National Lab., TN (United States); Dombrowski, D.E. [Brush Wellman, Inc., Cleveland, OH (United States)] [and others

    1995-08-01T23:59:59.000Z

    Beryllium because of its low atomic number and high thermal conductivity, is a candidate for both ITER first wall and divertor surfaces. This study addresses the following: why beryllium; design requirements for the ITER divertor; beryllium supply and unirradiated physical/mechanical property database; effects of irradiation on beryllium properties; tritium issues; beryllium health and safety; beryllium-coolant interactions and safety; thermal and mechanical tests; plasma erosion of beryllium; recommended beryllium grades for ITER plasma facing components; proposed manufacturing methods to produce beryllium parts for ITER; emerging beryllium materials; proposed inspection and maintenance techniques for beryllium components and coatings; time table and costs; and the importance of integrating materials and manufacturing personnel with designers.

  17. White Paper for Developing Electromagnetic Particle Injector system for ITER on NSTX-U University of Washington (19 July 2012)

    E-Print Network [OSTI]

    discharges in ITER, both the time response of this system and the controllability on demand - Conventional gas guns will inject gas before capsule and trigger pre rail gun We plan to finish the design during 2012 and to build

  18. A Pseudo Random Numbers Generator Based on Chaotic Iterations. Application to Watermarking

    E-Print Network [OSTI]

    Christophe Guyeux; Qianxue Wang; Jacques M. Bahi

    2010-12-21T23:59:59.000Z

    In this paper, a new chaotic pseudo-random number generator (PRNG) is proposed. It combines the well-known ISAAC and XORshift generators with chaotic iterations. This PRNG possesses important properties of topological chaos and can successfully pass NIST and TestU01 batteries of tests. This makes our generator suitable for information security applications like cryptography. As an illustrative example, an application in the field of watermarking is presented.

  19. Absolutely and uniformly convergent iterative approach to inverse scattering with an infinite radius of convergence

    DOE Patents [OSTI]

    Kouri, Donald J. (Houston, TX); Vijay, Amrendra (Houston, TX); Zhang, Haiyan (Houston, TX); Zhang, Jingfeng (Houston, TX); Hoffman, David K. (Ames, IA)

    2007-05-01T23:59:59.000Z

    A method and system for solving the inverse acoustic scattering problem using an iterative approach with consideration of half-off-shell transition matrix elements (near-field) information, where the Volterra inverse series correctly predicts the first two moments of the interaction, while the Fredholm inverse series is correct only for the first moment and that the Volterra approach provides a method for exactly obtaining interactions which can be written as a sum of delta functions.

  20. Design of irradiation rig for reactor testing of prototype bolometers for ITER

    SciTech Connect (OSTI)

    Gusarov, A.; Huysmans, S. [SCK.CEN Belgian Nucrear Research Center, 2400 Mol (Belgium); Meister, H. [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstr. 2, D-85748 Garching b. Muenchen (Germany); Hodgson, E. [Euratom/CIEMAT Fusion Association, Avenida Complutense 22, 28040 Madrid (Spain)

    2011-07-01T23:59:59.000Z

    We describe the design of an experimental rig, which was developed to allow reactor testing at relevant conditions, i.e. vacuum and {approx}400 deg.C temperature, of prototype resistive bolometers, which will be used in ITER to acquire information on the radiated power distribution from the main plasma and in the diverter region. The main feature of the design is that the rig has no active temperature control. (authors)